People often ask me where they should go in Lancaster. Here's my short-list off the top of my head on where I would go if I had folks who were visiting me from out of town:
Belvedere Inn - one of my favorites. It's casual chic, and sometimes the bar upstairs (called Crazy Shirley's) has a jazz session going on. Be sure to get their "grilled caesar salad." It's unique.
Carr's - Across the alley from Central Market. Most of his menu is really good. Only once did I go there and question his use of seasonings on a fish dish. Otherwise, great atmosphere and pretty good wine list. Upscale casual.
Lancaster Dispensing Company - across the alley from Carr's. It's a very casual joint that has great sandwiches. I would stay away from salads, and I have no idea about entrees, because everytime I go there, the wait staff tells me to get a sandwich.
Gusto's - New Italian/Mediterranean/Spanish place on Queen St. Although it has a wine list, you can bring your own wine for a $10 corking fee - but I think it's worth it; the wine list is pretty sparse. Their Veal Milanese (like a Weinerschnitzel) is the best thing on their menu. I also liked the carrot chestnut bisque, which was a special. Their pizza could be good, but it comes out soggy.
Rachel's Crepes - Casual cafe for crepes. It takes a while for the food to come out, but the crepes were very reminiscent of the ones I had in Paris - at least the egg and cheese one was.
Wish You Were Here - Total hippie dive. I like it for breakfast. They have good coffee, great Swedish oatmeal pancakes, and their Indian omelette is actually pretty good. They try to be organic and locally minded, which is a plus.
La Costena - Authentic Peruvian in a sparsely decorated place. Apparently, they have problems when too many folks are at the restaurant at the same time, so go during off-hours.