Thanks Joss, hcentaur13, and Dot_mdb!
Joss -- I will go with 24 inch monitor -- don't want to suffer dizzy spells from looking at a giant screen!

hcentaur13 -- I too enjoy using virtual desktops / workspaces -- had four at one time but am down to 2 now. Handy to help keep your projects separated.
Dot_mdb -- Great idea to run an ad. I'm always amazed at how well Linux runs on older computers. I think lots of thrift stores don't even take computers anymore because there's almost always something wrong with a donated machine and the customers get irritated by purchasing machines that don't run. Plus they take a while to evaluate -- as opposed to other electronics that don't have the complexity a computer has.
-Allen