If you haven't already done a forum search, try these threads:
http://www.roadfood.com/F...3&high=columbia+sc http://www.roadfood.com/F...8&high=columbia+sc http://www.roadfood.com/F...4&high=columbia+sc Little Pigs suffered a fire recently and is closed but rebuilding. Hudson's Smokehouse closed their location on Knox Abbott, but just moved into an empty restaurant in the Harbison Blvd area next to the Sam's Club; I still prefer the original location on 378 in Lexington. A new Rush's is going up almost across the street and opens in a couple of weeks. The Triangle City Zesto's is still your best bet but they sadly stopped serving the baklava sundaes and shakes. The Miyo's/M Cafe people opened a new location called M Vista--still pretty and still very good food, but certainly five dollars more than you need to pay for it. I would still venture into anywhere with 'Taqueria' in the name--my favorites are Jalisco and Mi Pueblito--rather than the other Mexican chains in town.
So for barbecue, take a roadtrip to Shealy's and maybe check out Hudson's--even the Hudson's buffet is pretty good.
For fast food, be sure to hit Rush's for a chili cheeseburger and a milkshake. Go to the Triangle City Zesto's for some fried chicken; I'm fond of the wing basket. Their milkshakes are pretty good too. Make sure to get to Rockaway's for a chili cheeseburger, and if hot dogs are your thing, Rush's, Edna's, or a location of Sandy's will do you fine.
Groucho's is good for a turkey sandwich with their 45 dip on the side. You really cannot go wrong with the Publix deli either--chicken fingers or they put together a nice sandwich. Oh, wait, Fifth Avenue Deli on Rosewood--we've dubbed it 'Ten Dollar Sandwich' but it's probably the best sandwich in town, and their ingredients are top-notch. They make killer egg salad and an awesome Cuban.
When I go out for dinner these days, it's often to the Hunter Gatherer. I hear they lost one of their cooks but so far they've held steady. Or sometimes I go to Old San Juan on Two Notch Rd for some Puerto Rican fare--fried plantains, mofongo, and their delicious beans.
Asian, I'm going to Sun Ming in Irmo, or occasionally Sakura on Forest for a bento box lunch. Right now we lack a really tight Thai place. There's some B-quality Thai places.
Pizza, don't get me started on pizza. (waiting for Chris to smile) I've become a pretty fair home pizza cook.
Oh, two new places I don't think I've mentioned before. The folks who operate the Mediterranean Tea Room on Devine (do not miss the broiled shrimp, only available at dinner--shrimp in a wine and butter sauce with tomatoes, olives, feta and jalapenos--yummm) opened a new joint on Taylor and Barnwell called Pita's and it's only open for lunch M-F, and it's terrific. Well, I had a cheeseburger there I didn't like once. But all their Greek stuff and salads are to die for, and if you happen to be lucky enough to walk in when they're baking, there's no better smell on the planet.
Breakfast is really the meal that Lizard's Thicket does best (don't miss the fish and grits); the Liz is a credible meat-and-three place but there are so many meat-and-three joints in the world that kick dirt in the Liz's face that I really can't blanket recommend it. It's fine in a pinch. Try the vegetable soup and grilled cheese.
Coffee joints, there's Cafe Strudel on State and another place two doors down. Sadly the big green empire closed down Adriana's in Five Points after twenty years. We do have several outposts of the big green empire.
Enjoy your time in Columbia!