I highly recommend the Triple Door to anyone who will listen (and I swear I'm not on their payroll), but I think that if you buy your tickets ahead of time, they'll make sure you get a seat (which I think is first-come first-served).

I know it can be pricey, but they really, really do treat you well there. I always get a good place to sit when I'm there and the waitstaff won't hassle you if you don't want to get a drink and will continue bringing carafes of water. Everyone there is always super-friendly (they even sent me a thank you card once!).