Bellagio is far and away my favorite book if you want to spend an entire day watching and betting on football. You want to make sure you'll be comfortable, and every one of their chairs is a nice leather recliner in a plush atmosphere. The cocktail waitress still came around pretty regularly, and I don't remember any drink ticket BS the last time I spent a day there (March Madness).
Problem is...you do have to get there early if you want a seat. A buddy of mine and I go every year and we get there at least an hour before any games. One of us will keep 2 chairs while the other goes and grabs some breakfast, plays BJ for a while, etc. Then I'll come back and hold the chairs while he goes off until gametime. It goes by pretty quickly, and since games start at 10am, you're not waiting around for very long.
I'm not sure who here likes Mandalay Bay, but unless you have a table reserved, you're going to be sitting on crappy folding chairs all day long (at least it was that way about a year ago). I've heard good things about Sunset Station...I definitely want to check that out soon.