Since I installed IE7, I find that other programs have slower screen updates. For example, one program where it is more noticeable is Freecel. On this computer, when I won and the cards all went to the top it was impossible to follow them because they
just suddenly seemed to all pop up at the same time. Now, I can definitely see that they are quickly going up one at a time.
The only thing that comes to mind is ClearType. I believe the setting is Inetcpl.cpl (Internet Control Panel) -> Advanced -> Multimedia -> Always use ClearType for HTML rendering.