Definitely ESPN, but a few words of advice from someone who worked there (and still works there seasonally):
Get there EARLY! Sports Central (the tables in front of the huge big screen, line on the left) fills up for MNF 2 or 3 hours in advance. No, you can't bribe the seaters (You can always give them money, but it won't get you a table.

). Once you get there, just get in line -- they don't take names, reservations or priority seatings. You must have your entire party present to be seated. It is first come, first served. Believe me, there's plenty of entertainment, you won't get bored if you get there that early.
Sidelines (the bar side, line on the right) is also first come, first served -- but you seat yourself. Booths fill up fast, so do cocktail tables. There's no shame in asking someone to share a cocktail table though, especially if they're supporting your team.
Another reason to get there early -- 99% of the time there will be a guest doing an interview show before MNF. 98% of the time it is someone from the NFL. No matter what, it's entertaining.
There is not a bad seat in the house. No matter where you sit, you will be able to see the game. Most likely on multiple tv's. You will be able to hear it throughout the entire restaurant.
Smack talking is encouraged. Wear your jerseys, hats and t-shirts. Have fun! MNF is one of the best parts of the ESPN Club, especially on nights when the Eagles or the Jets are playing. Their fans get rowdy and have a blast.