Here is a very good guide for Windows 7.
http://www.native-instruments.com/knowledge/questions/847/Windows+7+Tuning+Tips+for+Audio+Processing
Notice no suggestion to turn off indexing. I saw a very long discussion on Gearslutz that convinced me that the indexing service had been re-written for Windows 7 in such a way that it could not interfere with performance, and that you are better off leaving it on. I think with multi-core CPU’s, the benefits of turning off services that aren’t used often or at all is marginal. You can turn off what you know you don’t need, but you shouldn’t expect much difference in your DAW performance. Much more important these days is ensuring the power settings aren’t turning off cores, etc.