Refrigerator, that all you got? I bet the refrigerator is cooler than you, probably smarter.
Damn Lucy, I try and be nice and you give me shit. Well whatever, I don't want it, now you just keep it to yourself to roll around in.
Refrigerator is cooler than you = you are not as cool as a refigerator and might not be as smart as one either (he didn't mean literally cool, but she isn't as cold as a fridge, which would be a compliment.. calling her warm)
Give me shit, keep it to yourself and roll around in it = stop making fun of me when I am nice to you, please keep it to yourself
Literally he wants her to play in the shit (insults) she dishes out to him.