Brave and the Bold is quite good. There's a lot of little winks to comic continuity in there. For example- this weekend's US episode featured a meeting between the JLI and their cross-universal counterparts, the Justice Society. Aside from having R. Lee Ermey play a role, the actor playing Starman did the voice as Ted Baxter's voice. (See, Starman's secret ID is Ted Knight, who played Ted Baxter on Mary Tyler Moore. What? I laughed.)
Aside from that, try these:
Justice League/Justice League Unlimited - a great ensemble cast, with more Kevin Conroy Batman
Spectacular Spider-man / Spider-Man The New Animated Series (The later stars Neil Patrick Harris)
Wolverine and the X-Men
Movie-wise, I like most of the DC animated stuff, but the Green Lantern films and the JL films are probably the best. Marvel-wise, I'd only recommend Planet Hulk. The rest were meh.