I'd say that if the lighting is like most event venues I've seen, $700 of DSLR won't meet his needs either. As someone posted above, for most venues you need 200mm or better, and f/2.8 or better. I don't believe BB even sells a combination like that, and certainly not for $700. Since the OP doesn't have and hasn't had an SLR, they've got no idea of what to expect- and part of good advice is managing their expectations, not blindly answering a question. Heck, I've got tens of thousands of dollars worth of DSLR gear, and I'd still be thinking about renting a $200/week lens. $700 is a lot of money for the average person to spend to get blurry pictures.
Edit:
I'll give an example. I'm not an event photographer (I generally do fine art, portraiture and some product work,) but I'm pretty-well kitted out at this point. Last year, I was asked by a friend to take a few shots of a choir in the local cathedral. Despite having no lenses that weren't a fixed f/2.8 aperture and bringing along 3 AB800 strobes, I *still* had to have the video hot lights that they use for TV broadcasts turned on. I doubt they were more than a stop darker than most places that host amateur beauty pageants. Now granted, I had the run of the place, and if I'd not minded trying to reposition everyone and get my strobes into different positions, or if I'd brought my pack and head system I probably could have done it without the hot lights, but I'm guessing that parents of the contestants don't get that much access during the actual competition.
If he's lucky, the venue will be lit for TV- but that's a $700 gamble.