Today I've installed Ubuntu 12.10 (Quantal Quetzal). The system is solid; over few minutes of hands-on, one part that bothered me was the windows animation. As a software developer, I know, how difficult it is to implement animation. However, my machine is not fast enough to catch up with this, so, I thought to get rid of it.
This is how to do it:
First, install CompizConfig Settings Manager.
$ sudo apt-get install compizconfig-settings-manager
Then start the application. In Categories section, uncheck Animations and Fading Windows.
This would not make a vast improvement, however better. Hope this helps.