Sorry, didn't see this until now MS. Let me put it this way... I've brought friends down there on Vacation a few times now and it's the same thing every time. They get off the plane, go outside, look around in amazement and say "Why don't I live here?" Then it just progresses throughout the time they stay, especially once they hit the nightlife spots. I brought my Ex down there when we were together to show her around and she could not stop talking about how awesome it was after hanging out at all the best spots downtown. The food, bars and clubs are simply unbeatable.
You have the Gaslamp District, which as of the last time I went down there is even better than I remember. That's about as classy and awesome as you're going to get anywhere outside of NY or LA, but with more of a laid back vibe. Then you have the Beaches... Pacific Beach is really the only one worth getting into here, but there is a lot of them. PB is amazing... I lived there for years. Amazing beach, women and a strip of bars that will make you question even going downtown that night. But do both. I recommend Moondoggies, PB Bar and Grill and really any of the places on that street.
As far as TJ, I would have recommended it for a fun time like... 8 years ago, maybe. But not now. Drug wars have spilled over to Revolution. It's a legit dangerous place. But if you do decide to go, visit Sufari's or Mr E's... Both in the same building.
Pro-tip: Ask for Dave the Manager at either location and tell him John sent you.