Everyone will be able to find something on the menu at Madhouse Cafe, a wonderful New American/Fusionish place in downtown Pawtucket in the Apex Building.
For lunch, I'd recommend Jac's Wraps on East Ave. Just get off Exit 27 on I-95, go down the street to pick up your lunch, then double back and head to the stadium.
As mentioned Chelo's: http://www.chelos.com/
Madhouse - http://madhousecafe.com
Gregg's - http://www.greggsusa.com/ North Main St
Bertuccis - http://www.bertuccis.com/ Newport Ave
There is an Olive Garden in Attleboro, that isn't all that far from the stadium.
Mama Spumoni's just down the street from OG on Newport Ave:
All pretty casual with okay food which I'm guessing you are looking for.
In "downtown" Pawtucket there is also China Inn that used to be good - not far from Madhouse.
Just remembered there is a Ground Round too - you can see it from the highway, just around the exit for the stadium.
None of the places mentioned are more than 20 minutes from the stadium depending on traffic. I have no idea how traffic is on game day.
(Just a funny side note - I'm going to be in NJ soon, went to the board and saw Pawtucket, I was like what? and saw your oops!)
So hope our posts have helped.
Have a great time at the game.