Well Dad came into town 2 weeks ago and I went through his computer. Surprisingly everything appeared to be fairly intact. He lost all of his email, bookmarks, and documents... but all the programs I put on there worked fine.
I went ahead and set up 2 AIM accounts so we could do iChat. Did the share screen thing for the first time today and it worked like a charm. So much easier to troubleshoot when I can see his desktop and talk at the same time. Really appreciate the suggestion... worked great!