R. Star wrote:
If you're looking to jump into the franchise with TOS, I'd recommend starting with the movies as I said earlier. It'll give you a chance to get to know the crew without the random episodic format as movies 2-6 are pretty much one continuous arc, each picking up after the last. Hope that helps.
Agreed. TOS movies 2-6 also contain a few of the best Trek movies ever, in my humble opinion. But, I would recommend watching the TOS episodes first. There are some real gems in there.