I only saw the Fourth and Fifth Doctors as a child and my memory is sketchy so I can't offer any recommendations. I'm happy that you're watching old Who (or at least giving it a try).

I plan on collecting some old Who dvds or something when I can actually spend money frivolously again.

Anyway, I recommend anything with Four (played by Tom Baker) or Five (played by Peter Davison)

I know I haven't been much help with recs, but those are my thoughts.

If you have a specific Doctor that you want to see (or any episode), let me know and I'll try to find it.