Note that "Superfetch" takes a few Boots before it "optimizes itself" -- I'd switch this off as well as the "fast Search". I'd also disable the Readyboost --you don't need this with 6GB RAM so disable the service.
Superfetch is not really necessary and indexing whilst it does improve the speed of finding a file etc the overhead of it running almost continuously IMO isn't worth it. How often are you really searching for files --if you do this a lot either organize the way you work differently or consider using something like a proper cataloging system or a database like MySQL.
Cheers
Jimbo