"Teen Titans: Boogie Tights": Everyone's born with one special thing.... especially Dick Diggler (no wonder they call him Boy Wonder!) This Boogie Nights / Teen Titans mash-up was done as a tribute to movie critic extraordinaire, Roger Ebert.
I think I remember the X-Men/Teen Titans crossover where both teams had to deal with the Dark Phoenix and both Deathstroke and Darkseid. Robin helped to diffuse a tense situation where Starfire reflexively attacked Beast Boy when he accidentally brought up memories of the Dark Phoenix by turning into a representation of it. He agreed to help her if they found the Dark Phoenix (and refocus their attention to it), but return to their original mission of finding and stopping Deathstroke if they couldn't. (They found both in the same place, as well as Darkseid.)
So let me try and match each character to the actor: -Robin/Mark Wahlberg -Starfire/Heather Graham -Donna/Julianne Moore -Beast Boy/Phillip Seymour Hoffman -Wally/John C. Reilly -Deathstroke/Burt Reynolds Aaaannnd I can't figure out the rest.