In my case, I had to have an intervention to switch my parents over to a Mac. The Dell they had was overflowing with viruses and spyware and I'd spend a day or so cleaning it off only to return every 6 months and repeat the exercise. It was slightly easier to make the transition because a few of my mom's friends have switched.
After a year of trying I got my dad to switch to a Powerbook a few months ago. A few weeks ago he called and told me I need to get one too. That was a joyous phone call. I find out I'm finally getting a Mac and get to gloat about being right.
My dad first bought a Timex 1000, and later bought a second one for $10 somewhere. Those are still around. His next computer was an Apple II GS, which he used for six or seven years. The next one was a Mac Performa 6360 (a "pizza box Mac") which is a pretty good box if you pull that BS modem out of it and hook up an external one. Had a hard time talking him into doing that kind of thing. His last computer, about six months before he died, was an eMac.
I had to talk him out of getting a Wintel before the GS and before the 6360, and various other times. My argument was that he would probably rely on me a lot to fix things and the like, and that I had more experience with Apples. When I pulled the 6360 modem and hung a nice 56K external modem on it, he used it for a while, then had some puzzling hangs, took the system to a supposed expert shop specializing in Macs, and came home with ANOTHER slow internal modem. Same troubles emerged. We pulled the second modem, and I gave him an L2 cache I tracked down, and we upgraded his hard drive at the same time. The L2 card went spla about a year later, so we pulled that. He finally made noises about getting a new box.
It's still possible to get the Sonnet accelerator for 6360 et al, and I've been thinking about that. Also, Sonnet now has a 1GHz upgrade for the PCI Macs (I've also got a 7600) and I'll probably do that pretty soon. That one has more RAM than my usual machine (a rev b iMac, 233 Mhz), and can easily be expanded.