killing alt + tab. cant :(

[luv2liv]

when i hit ALT+TAB on the keyboard, this pops up.
how would i kill it?

sure its convenient to preview apps before they appear, but it takes a lot of system resources. i installed it for curiosity but have no idea how to uninstall it.

 

[Jackhamr60504]

It is part of TweakUI from Microsoft, if I remember correctly.