I'm new here, but this is an area of my expertise! Of course, I'm sure others have made lists online, but I will make a little list here of my personal favorites.
In Annapolis, I would recommend (and these are not high-priced options):
McGarvey's if you like and/or are interested in oysters and crab dip. O'Brien's if you want something a bit more sophisticated, but pricier.
Chick & Ruth's for classic breakfast food, milkshakes and to visit a classic 'Man Vs. Food' location.
If you have a sweet tooth, check out Kilwins.
The Naval Academy has good 2 hour tours.
Not everyone's cup of tea, perhaps, but the Maryland State House is usually open to the public and can be fascinating to explore.
Gameday
Be sure to get there early - the tailgating scene is surprisingly bustling and roads near stadium are narrow and crowded. Solid shuttled lots and free street parking options.
Weather permitting, try and get into the stadium about an hour before kickoff to see the Mids march on to the field.