Check out Dino's for a cozy atmosphere and good italian food:
Dino's Restaurant, Worcester Mass
If you like seafood and don't mind spending some money, the Sole Proprietor is worth the visit:
The Sole Proprietor
If you want Teppanyaki (think Japanese steak house), try the Sakura Tokyo:
OurMenu
I've also been partial to Ciao Bella for informal occasions when I want italian food.
For really informal, Coney Island hotdogs are fantastic!