Last year was my first time at Gencon, I'm planning to go this year.
Regarding hotels......for your first year in Indy, yeah, stay downtown. But if you plan to return, look for much better deals a bit further out.
Regarding the Ram....I couldn't even get in the door without being quoted a wait of 45-50 minutes. I never got the chance to eat there. The staff at the door was rude and had NO control over the situation at the door. Forget it.
Regarding the dealer room....you know whether or not I buy something, it's cool to talk to some of the people I do business with or see on message boards or write some of my favorite stuff. I met Jolly Blackburn, Kevin Siembieda, some folks from Mongoose Publishing, some folks from RPGObjects, folks from Chessex, and others. It was very cool. I picked up some books I never would have even seen without the company having a booth at Gencon. I was made some great deals on books too. Call me kooky, but I like hearing people talk excitedly and enthusiastically about their livelihood. I walk through everyday seeing people who take no enjoyment or pride in what they produce, it's wonderful to see someone so passionate about a product and it's an infectious feeling. Wander the dealer room, talk to booth folk, seek out deals, and watch for new stuff.
General advice...
-dress properly. It's hot...I mean really HOT and HUMID in Indy in August. Shorts, skirts (of appropriate length), light shirts, t shirts, comfortable, cool shoes.
-keep hydrated. buy one water bottle, then keep refilling it throughout the day.
-seminars. try to attend some. They're a nice change of pace from gaming/anime watching/dealer room shopping/etc. they're pretty interesting too.
-pack sensibly. take into consideration that you will be bringing back swag and make allowances in your baggage for the additional weight.
-if they have a dance, skip it; find an RPG pickup game. every song was this techno crap, the band played nothing recognizable, and there's wasn't a ballad or slow song in the bunch.
-get some kind of decent sleep at least one night.
-eat at least one good meal a day.