1st Ave around 17th street - where to eat?
Mumbles Restaurant on 17th Street & 3rd Avenue (212)477-6066 is exactly what you describe: not too hip, comfortable and decent eats. They attract a neighborhood crowd and also offer a pre-fixe special from about 5 to 7 p.m.
Piccolo Italian Restaurant on 19th Street & 3rd Avenue (212) 420-0600 is a small intimate place that I enjoy when I'm in that area.
You might want to also see what's below 14th Street & 1st Avenue. There are lots of small restaurants. Around 12th Street & 1st Avenue is a Polish restaurant on the west side of the street (can't remember the name) which has a back garden that has excellent blintzes and soups.
Hope this helps.
Second and 19th has a good Italian...can't recall the name.
Posto for thin crust pizza on Second and 18th. Better than most.
Third Avenue and Irving Place have more of a selection:
Rolf's (German) on 22nd and Third
Molly's for burgers
Pasta place corner of 22/Third
Pete's Tavern 18th and Irving
Friend of a Farmer 19th/20th and Irving