Hi Douglas

Must have been a RAM salesman you spoke to at Dell.!!!
I do not see any point in spending money on 4GB of RAM if your OS cannot use this much.
Yes, you will get the benefit of increasing from 1GB to 2GB,but going above that is not really going to give you value for money.
As Kemical says, your 32bit OS can only read between 3-3.5GB of RAM, so putting in more is throwing money away.