To get the behavior you want you need to do a few things in addition to stopping the pop-up delay:
Install CCSM if not installed already. apt-get install compizconfig-settings-manager
from the terminal or search for "Advanced Desktop Effects Settings (CCSM)" in the Ubuntu Software Center.
Select the System Settings option in the power button menu (top right corner) and launch CCSM from there.
For Ubuntu 13.04 (Ringtail)
This may also work with > 12.10; unfortunately Unity changes significantly between versions.
Select the 'Ubuntu Unity Plugin' in 'Desktop'.
Under the 'Switcher' tab un-tick 'Show live previews of windows in the switcher'.
I'm not sure the popup delay exists in 13.04; I don't seem to notice any on my machine at least.
This section also allows you to swap the bindings of the switcher for all viewports and the viewport switcher.
For Ubuntu < 12.04
Select the Static Application Switcher in 'Window Management'.
Under the 'appearance' tab check 'icon' and 'show icon only'
And as @fossfreedom said, you can get rid of the .2 second delay "feature" under the 'behavior' tab by reducing 'popup window delay' to 0.
If you don't want them in rows you can switch to the 'application switcher' and change the settings similarly. Just make sure you do this by de-selecting the 'static application switcher' first, or else you'll get binding conflicts.
Best Answer
I don't know of any way to change the colour of the alt+tab switcher in Unity, but you can use an alternative in Compiz. Let us look at the alternatives:
Before we start:
Create a nautilus script to reload Unity when ever it crashes:
unityreloader
. This will restart Unity so you don't have to log out and back in.Install the extra Compiz Plugins: Compiz-Plugins-Extra .
Shift-Switcher:
This plugin is not perfect, but it is rather aesthetically pleasing. By default, it will have some minor conflicts, so you will need to change the keyboard shortcuts. Please not that any keyboard shortcut using super will probably cause problems or fail to work because Unity uses this for many actions.
Ring-Switcher:
Similar to the Shift-Switcher, however by default it exits when you release the shortcut key.
Scale:
If configured correctly, Scale can be used to show all windows on the workspace (or all workspaces).
NB:
The following two caused Compiz to lock up on me when I enabled them (though they work after logging out and back in again) - use at your own risk:
Application Switcher and Static Application Switcher:
The most basic of all, these two are similar to the default app switcher, but show text colours correctly.