could try Process lasso , it stops background progs hogging the resources by throttles um if they get too greedy
, most effective when using a low powered computer, I used to use it on a 1 gb ram netbook windows 7 starter, and it made it run nice and smoothly and stopped periodic freezing.
free version
download 32 or 64
Process Lasso - Automate and optimize priorities, CPU affinities, power profiles, and much more!
could also try cc cleaners / tools / start up - and make sure ther'es not a load of crap starting with the computer .
Then restart computer