Star Trek! Really, I agree that both are great, but I've been a life-long Trek fan. I've seen a lot of the original series, watched The Next Generation and Voyager several times through each, watched all of Deep Space 9 once, Enterprise once (but that series didn't last as long), and I have a lot of the movies. Star Wars is considered one of the best movie series ever, but Star Trek has spanned decades worth of amazing TV series.
The recent reboot movie was great, and I can't wait to see Into Darkness! I've been meaning to see it since it came out, but haven't gotten around to it yet.