@doomwolf: It will save you $30 (it's just gone up from $20 I believe) and my advice is this: get there early as anytime after 0900am on that day, or on a public holiday weekend, the queues to get into the park can be immense. I was driving out one public holiday weekend and the queue to get in was 3 miles. The Lodge is good and I am sure you will like it.
As for the Ahwahnee - definitely worth a wander around and dinner and/or lunch there. The pizza patio at Curry Village in the evening is good too. I am not keen on the buffet at Curry Village though so would not recommend that.
@OP - I would try and stay in the park if possible, Yosemite Lodge is good, Ahwahnee is best, Curry Village hard sided cabins are OK (I used to really enjoy them but got older and decided my days of roughing it are over!). Don't be despondent if there is nothing available as persistence is the key and if you ring up you may get a cancellation. Their cancellation policy is, I think, 72 hours without penalty and a lot of people leave it right up to the wire to cancel so I would start calling daily from about a week out, and about once/twice a week from now until then. We have always had success doing that.
The NPS website for YNP has some good info to help you plan:
http://www.nps.gov/yose/index.htmGlacier Point, Olmstead Point, Tenaya Lake, Tuolomne Meadows, as well as all the Yosemite Valley Floor normal stuff, is well worth it. If you have a small pair of binos then take them to watch the climbers on El Capitan if there are any while you are there.