Sporadic On and off Freezing?

I have a macbook pro brand new pretty much
2 gigs of memory
250 gig 7200 rpm
2.4 ghz

It's spiratically freezing on me. It's not a complete lock up though, it's on and off. It's like freeze count to 5 unfrozen count to 5 frozen again endlessly. I've clicked in my dashboard and checked my statpro and it says I'm only using like 50% of the memory, 50% of the harddrive space, and like 50% total usage... so why is it freezing and how can I permanently fix the issue?

go to utilities and then activity moniter, are there are any activities running unusually high?

Not at the moment. Although unfortunately it's not freezing atm. It happens most when I do certain things. Like VMWARE Fusion = death, and sometimes Adobe Photoshop CS3 causes it.