As I noted in my New Who skip/watch list, it can be intimidating knowing where to jump into the new show, with its 13 seasons and five (or seven, depending on how you count) Doctors. But this is nothing compared to Classic Who, which lasted 26 seasons and seven (or eight, depending on how you count) Doctors.
The good news is that Classic Who really isn't reliant on over-arching storylines, so it's easy to jump in with any Doctor. The bigger question is where the most appealing starting place is. Because of the show's wildly differing quality (and, admittedly, often dated SFX), it's important to choose a strong starting point. Once you're hooked on the charm of the cast and the whimsy of the premise, it's much easier to overlook silly things like "budgetary constraints" and "cheesy dialogue" (mostly).
First of all, a word about format. If you're familiar with the new show, you'll be expecting quick 45-minute adventures. In Classic Who, almost every adventure is four or six 25-minute episodes long. This allows for much more epic, in-depth story-telling in some cases, and in others, it means a lot of filler. You'll get used to the pace, you just have to settle in for a while. Now, I get frustrated with the rocketing pace of the new show!
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