My son LOVESLOVESLOVES watching Elmo DVD's. It's a bit annoying because once the DVD is done (45 min long) he wants to watch another one and whines when he doesn't get his way (I think he's bored of all his toys). Despite the fact that I'd be able to get some work done, I refuse to let him watch TV all day long.
Anyway, I watch the DVD's with him sometimes and that Elmo is a crazy bird. I saw the one on singing just today and he impersonated the 3 Tenors, Elvis Presley (complete with blue suede shoes) and a rapper (rapping his "Elmo's World" theme song). On another one that talks about sleep, a flying talking bed comes into Elmo's house. The mattress does the talking and the pillow agrees with him by saying, "You tell him, beddy boy" over and over. It's really pretty entertaining, sometimes even for adults.