The color of selection elements in themes used by Ubuntu 12.04 is determined by a single value and is therefore the same for all of them: highlightened buttons, files, menu items as well as the selection box that you get by holding and dragging your mouse.
You can set this value in the settings.ini of each theme. The settings file of the Ambiance theme for example is located in /usr/share/themes/Ambiance/gtk-3.0
Before you edit the file, create a backup copy of it in case you want to reset the theme to its original state. Just copy the file somewhere else to do that. Afterwards, open the original file as administrator. This is easily done using the terminal:
sudo gedit /usr/share/themes/Ambiance/gtk-3.0/settings.ini
The value that determines selection color is nselected_bg_color - it is formated as hexadecimal value (#000000). You can now use a graphic editor to find out the hexadecimal value of the color you want to use - if you wanted to use red for example, you would have the value #FF0000.
Afterwards save the file and log out of your current session. After the next login, all elements of selection should now have the color of your choice:
Hibernation is disabled on Ubuntu 12.04 and Mint 13 by default - you can only access it with the command line. To have it as an option in the shutdown menu again, open a terminal and enter the following:
sudo gedit /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla
By that you create a new text file. Paste the following into it:
Save the file afterwards and reboot. Hibernation should now be an option in the shutdown menu again.
To uninstall VirtualBox Guest Additions on Ubuntu and similar operating systems, mount the virtual disk again that you used to install them - to do that, click on the Devices menu on the virtual machines top menu bar and select Install Guest Additions. If you get a pop-up about auto-start procedures just cancel it.
Now that the virtual disk is mounted, open a terminal and look for the contents of the disk in the /media folder.
In my case, the disk is named VBOXADDITIONS_4.1.10_76795. This name may vary depending on the version of VirtualBox you have installed. Now uninstall the guest additions (don't forget to adjust the path):
sudo sh /media/VBOXADDITIONS_4.1.10_76795/VBoxLinuxAdditions.run uninstall
You can uninstall the guest additions just like any other program on a Windows machine: Click on Uninstall a program in the Control Panel and search for the version you installed. Select it and click on the Uninstall button above the program list.
If you are one of those who like to deal with inserted DVDs, USB keys and other removable media yourself, the Autoplay feature of Windows will most likely do nothing but being clicked away by you.
If you want to save yourself a pop-up and a click you can disable Autoplay. To do so, open the menu and type in gpedit.msc. The group policies window will open and you'll see a navigation pane on its left. Browse it for
Local Computer Policy > User/Computer Configuration > Administrative Templates > Windows Components > AutoPlay Policies
Pick User or Computer Configuration depending on the range you want your settings to have. On the right pane, there should now be some settings, on of them being Turn off AutoPlay. DOuble-click it for the configuration window to open.
On the left, click the Enabled radio button. On the options pane you can choose between turning AutoPlay off for all media or just for CDs or removable media drives (since those are the most common I'd recommend to choose that). When you're done, click Apply and exit the group policies. Next time you insert something you won't be bothered with pop-ups.
VirtualBox offers a feature that let's you treat windows opened in the running guest system almost as is they were native to the host system - you can drag them around on the host system, copy and paste texts between the system and only see the host's desktop while doing so:
The requirement for Seamless mode to run is that the VirtualBox Guest Additions are installed. You can quite easily install them by clicking on the Devices menu on the the guest system's window menu and selecting Install Guest Additions... - follow the installer afterwards and reboot the guest system when you are told to. After the reboot you can enter Seamless mode by selecting the guest system's window and pressing right Ctrl + L.
Whether you want to use Metro in all its glory is up to you of course but for those who want avoid this interface as thoroughly as possible, version 3.5.1 of ClassicShell brings a useful new feature: it can now get you around the first instance of the metro startscreen that you are presented with directly after login. Combined with its formidable start-button it makes Windows 8 look nearly like Windows 7, saving you the muddle of learning how to use a touch-interface on your desktop computer.
To install ClassicShell 3.5.1, download it from http://sourceforge.net/projects/classicshell/files/Version%203.5.1%20general%20release/ClassicShellSetup_3_5_1.exe/download and follow the installer.
The startscreen should be disabled by default - if you just want the start-button, you can turn on the start-screen again by opening the menu and selecting Settings > Classic Start Menu. Afterwards click on the All Settings radio button ond go to the General Behaviour tab.
To enable Metro welcoming, deactivate the Skip Metro screen checkbox.
German keyboards are usually QWERTZ keyboards, named after the first line of letters up to the first that differs from the English layout, which is QWERTY.
You can switch between these two using the key combination Alt + Shift.
This switch may be the cause of your keyboard behaving strangely - for example if you pressed the combination by accident. In this case z would be replaced by y and nearly every special character would be mapped differently. Try to switch layouts if you experience that.
Windows as well as other platforms use two different forms to display a text-cursor. One, which is used most, is the bar-formed cursor which rests between two letters. The other has block form and rests on a letter, replacing it if new input is done and going one letter further. This is annoying if you activate it by accident.
You activate as well as deactivate it with the Ins key on usual keyboards. If you are using different hardware, look for a key combination equivalent to the Insert-key.
Since every aspect of Linux is customizable, so is the terminal. Why not spice it up instead of working on a plain white box?
To do so, just open one and go to the Edit menu where you select Profile Preferences. This changes the style of the Default profile. In the Colors and Background tabs, you can change the visual aspects of the terminal. Set new text and background colors here and alter the terminal's opacity.
On the other menus, you can create more profiles that you can save and also change fonts.
Virtualbox, as most other virtualisation technologies, provides a service to establish shared folders between the host system and the virtualbox guest OS. For that, you need to install the Virtualbox guest additions. To do so on virtual desktops, just open the Devices menu and select Install guest additions....
Mount the CD and proceed like you are told to install the guest additions (steps differ in Windows and Linux). Before you can mount a shared folder you first need to create and/or assign one. Open the settings of the Virtualbox you are running and select the last menu item from the left pane, Shared Folders. Click the icon with the plus symbol on the right to assign a shared folder and give it a name, I'll use the name blabla for future reference. After assigning a shared folder you can mount them on your virtual machine.
On a Windows machine, open a cmd terminal and enter following (replace my folder name with yours):
net use x: \\vboxsrv\blabla
The folder will then be accesible from the Computer directory.
In Linux, open a terminal and enter following:
sudo mount -t vboxsf blabla /mnt
You can replace /mnt with any mount directory you like, of course.
The shared folder is now set up. You can push files there from the host or the guest system and access them from the other, which makes connecting both much easier than setting up an FTP or SSH connection.