from another friend;
I'm using the same machine as your buddy Gregg and had a similar problem. It became so bad that I contacted Apple, thinking my HDD might be failing.
They suggested resetting the PRAM and NVRAM, which certainly helped. I think the minimal 4GB RAM also contributes to the problem and I will be adding more to mine shortly, in the hope of gaining extra improvement.
Instructions for resetting the PRAM and NVRAM at:
Intel-based Macs: Resetting the System Management Controller (SMC)
About NVRAM and PRAM
Hope this helps.
Michael Jahn - Slightly used PDF Evangelist
Simi Valley California