Windows Vista's Aero looks and effects are generally nice to look at, but when you're trying to squeeze the last bit of power and life out of a battery, or just running some memory-hungry stuff, you don't always need them. You can make to add "Aero On" and "Aero Off" shortcuts to your desktop right-click menu, making it simple and quick to toggle.
Run REGEDIT and go to HKEY_CLASSES_ROOT\Directory\Background\Shell. Right-click the Shell part, select New > Key and call it Aero On.
Right-click the Aero On key you’ve created, and create a new key called command. Double-click this (in the right-hand side of the screen) and give it the value Rundll32 dwmApi #102.
Right-click the Shell key again, select New > Key, and call this Aero Off. Create a command key below it, as you’ve just done, and give it the value Rundll32 dwmApi #104.
Now, right-click an empty part of the desktop to see your options, and select Aero On when you want fancy effects like Flip 3D, and Aero Off when you’re after raw speed.