blues club with decent food NYC
I can't speak to blues specifically, but a great jazz club that sometimes features blues musicians (and has GREAT food) is the Jazz Standard on 27th street off Park Avenue. Their restaurant upstairs, Blue Smoke, is fantastic, and they also have a great menu downstairs where the music is.
Other than that, BB King's is all I can recommend!
Park Avenue Cafe
100 E 63rd St, New York, NY 10021
116 East 27th Street, New York, NY 10016
check Delta Grill on 9th Ave and 48th. it's a New Orleans style restaurant with live blues on Friday and Saturday nights, as well as during weekend brunch. my absolute favorite place for food and music is City Winery, however, the focus is on the music. they get well known musicians, so tickets are often $35+. their food is definitely Chowhound worthy though, as are their wines.
700 9th Ave, New York, NY 10036
155 Varick Street, New York, NY 10013
honestly, i've only been to Delta a few times when a band was playing. i used to work nearby and went for lunch quite a bit. the bit that i heard was all blues, though.
if you do go, i recommend the Chicken Lenore...breaded cutlets stuffed with andouille sausage and served with mashed potatoes.