Agreed. If you get a single-tuner Series 2 Tivo, then whenever your program comes on to record it'll switch the tuner to that channel (so you don't have to worry about your parents trying to figure out how to switch between tuners). That's the only way I can think of to make it automatically switch to the channel at the right time. Well, other than buying a Philips Pronto, which can be set up with timers to carry out macros (I used to use mine as an alarm). But then the remote has to always be pointing at the screen.

I think Tivo is the way to go. My mom is a total technophobe, but she was able to master the Tivo in less than a couple weeks. She's not getting as old as it sounds like your parents are, but if she were I think she'd still get along well with the Tivo.