1st off get rid of Mcafee it's terrible on a computer.. it eats ram like it's brunch.. you should chose a better alternative.. CA-Antivirus is in my opinion by far the best out of the bunch and it only uses a little ram compared to Mcafee and Avast and others out there.. Especially Norton, Norton will destroy a computer fast..
Boiler it's probably locking up due to lack of ram, if it was me I would go an virtualize your ram.. Actually back track that statement what I would do is when you Reinstall Windows make two partitions.. Make Partition C: for your storage and stuff and make D: for your actual windows installation.. it will make things run much more smooth as Windows won't be required to constantly search and run and look for things in the Virtual Partition.. I did this on my Vista and boy with 8 gigs of ram and a Virtualized OS she runs quite a bit faster.. Now if only I could over clock my Quad Core AMD to 4.5GHZ a core... we would be all set!

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Past: 95 Dodge Neon 2.0L Stage 4 Turbo (Street Tuner) *Wrecked/Sold*
Present: 05 Jeep Liberty (KJ) 2WD 3.7L, LTT CAI, Weight Reduction, SS Ultra Lights, and many more mods
If I don't stir the pot then no body will and the world would be boring, watch this guy for extreme sarcasm though
