Just to follow up...I didn't get nearly as much money for Christmas to spend on a computer as I had hoped for.
As a result, I've been unable to follow your suggestions. I settled on a refurb from Newegg which I believe is three years old. They would not add more memory for me, but I expect that won't be a problem down the road.
There are two programs I want to buy, both requiring 1 meg memory, and this should do the trick for them.
http://www.newegg.com/Product/Product.aspx?Item=N82E16883155189
Thanks again for your thoughtful suggestions.