I've shot my kids preschool programs with the following setups:

Nikon D800 with 80-200mm f2.8, 1080p 24fps (bluray): $3k camera, $500 lens, $60 monopod: great picture, when in focus. AF is slow, best to use manual focus. Low light and depth of field are the DSLRs greatest virtues. It's still a lot of money for a kids program. I'd only recommend it if your serious. Sure you can get a $500 costco kit, but the zoom lens isn't as good in low light nor is the camera handling any better. Not to mention the CMOS jello effect.

Camcorder: cheap, easy, quick. The AVHCD format is a beast if you ever want to edit, and it shows Artifact ing, while the jello effect is more subdued. Cost: $600.

Olympus Tough: ($300), every bit as easy as my camcorder and much more user friendly than a DSLR. The DSLR and Olympus tough will require a monopod, while you can get away with hand holding if you have a good camcorder with straps

Now, if you are a still shooter first, by all meAns get the DSLR!! But if you just want videos, it's tough to justify a DSLR for purely it's video capabilities. It's expensive and a tad cumbersome.