Obviously the home opener
You can stay anywhere in Buffalo... it's very easy to commute around the city. I recommend Adams Mark Hotel or The Avant if you want to spend a little more money
Things to do? Tailgate, Niagara Falls, Clifton Hill (Canada), take a stroll through downtown, visit the Harbor, Galleria Mall, and of course enjoy the Buffalo food! I would also recommend walking down the Elmwood strip and check out some shops... maybe even go to the Seneca Casino if you're into gambling.