I think specifically he wants me to see the third and fourth, since they're his favorites. Guy's frickin' obsessed with Tom Baker.
As he should be. Tom Baker's fucking amazing. In fact, he's usually the one I recommend when people say they want to get into Classic Who.
Cuz like, here's the thing, I've seen so many people try to watch the very first episode of Classic Who, and then give up shortly after that because they just can't get into the early episodes, and don't want to slog through them all in order to get to the obsessed-over legends like Tom Baker. But see, there are some good reasons why the early episodes come off as such. Not only did the show have the budget of a ham sandwich, all while being really experimental and having no idea what it wanted to be (thus leading to some
weird episodes), but, probably the most important thing,
TV was very different in the 1960's than it is today. The pacing, in particular, was a lot slower back then than today. Which doesn't really make it
bad as much as a product of the times, though it would feel really slow to someone more used to today's TV. It's basically a culture shock, and it's too much for most New Who fans to deal with, which is why they can't get past the earliest episodes.
Therefore, I usually recommend Tom Baker (or, hell, Jon Pertwee, the Third Doc, is another good place to start, too), because, while it is still very different from New Who, it's not
as outrageously different as the early Hartnell episodes. By this point, the pacing is easier to adjust to, the show's found more of a rhythm and knows what it's doing, and the budget/effects have improved. I mean, a lot of the effects are still pretty laughable, admittedly, but they've moved past the point of cardboard spaceships held up by visible strings, so, that's an improvement.
Also, Classic Who is easy to jump around with, so you can just sample some of the mid-Classic-era Doctors like Three and Four and then go back and watch the others later. While New Who places a bit more emphasis on season-long arcs, Classic Who almost never does. Each story is rather self-contained, so you can pick up just about any Classic Who DVD off a library shelf, for example, and not be confused.
Speaking of which, I should probably explain the arc format. See, while New Who episodes are usually 45 minutes and sometimes two-parters (but usually not), Classic Who has 24 minute episodes that are packaged into tightly-linked arcs that are usually 4 episodes long. So, one Classic Who story is spread out across a number of episodes in the same way that a two-part story in New Who would be. That's another reason why so many people give up so quickly when they don't understand the arc format — you get to the end credits and think "What? Hardly anything happened", but that's because part 1 of most arcs is mostly exposition. There's a ton left to watch. I mean, given how long these arcs are when you watch them in one sitting, watching only one episode in an arc and judging it based on that is basically the same as watching the first 24 minutes of a Sherlock episode and doing the same with that. Each story is best viewed as a whole.
In fact, if you have access to any hard copy DVD's (I recommend checking a local library), each DVD is just one arc. Hence why you can pick up any Classic Who DVD and start watching just fine, since you don't need to know a ton about what came before it. Sure, you might not know a ton about how the Doctor met whatever companion he's currently traveling with and that might add more to the story, but, hey, that'll just make it even better upon re-watch. You can always go back and watch stuff in-order later, but, when you just want to get a taste for all of it and get used to how different it is, it's best to just sample a bunch of different stuff and go back and watch chunks of it in-order later.
Edit: Actually wait, the Third Doctor's era has slightly stricter continuity than the Doctors before and after him, since there's sort of this whole over-arching story about how he's stranded on Earth for his first few seasons cuz the TARDIS is broken and he has to figure out how to repair it, so he winds up working for UNIT and helping them with their alien nonsense in the meantime, so... yeah. Fair warning on that part.
