Had the same thread for Vista once, and now for Windows 7 what major features/service did you turn off in W7?
System Protection (Restore) -> Until I get a bigger harddrive, I’ll keep it off. It is space chewing and there are so many good free backup utilities there, I use Easeus backup personally and Macrium sometimes.
Windows Search (Indexing services) -> Search will be fast as long as your files are organized and the condition is okay.
Windows Defender -> NOD32 is fine.
How about you guys?