Hi,
Depending on your budget, I'd look into the Bricktown area for hotels. The Sheraton is a very nice hotel in the area, with lots of restaurants, bars/pubs and entertainment close by (it's also close to the OU Medical Complex if that is where you're going for treatment). There's also the local NBA team (OKC Thunder) within walking distance to the arena if you'd like to catch a game.
For more restaurants, bars/pubs, you can check out the Midtown, Paseo and Plaza Districts as well.
I live in NW Oklahoma City. If you would like more specifics, please let me know and I'd be happy to assist the best I can.
Cheers