That is ALOT of time to kill in Lexington. i used to struggle to find something to do in Lexington for the 1 hour my DD had gymnastics class. If you have 4-5 hours, and a car, you ought to drive on down to Asheboro (about 20-25 minutes down 64) and visit the North Carolina Zoo.
One thing in Lexington that is kinda cool are the pig scultures downtown--they're decorated to reflect businesses, etc. So they have a barrister pig in wig and gown; a pig in pjs, a sports bar pig--can't think of all of them, but that is pretty good to kill about 15 minutes. Further obsure interests in the area include Thomasville with the "world's largest chair" and High Point with the "world's largest chest of drawers" There is also a doll museum in HP, but all those dolls looking at me creeps me out, so I only visited once.
as to the barbeque: it is tomato based with ketchup. The most famous place to eat it is Lexington Barbeque on business 85; but most locals go to Speedys which is on 52 towards Winston (much larger portions). There will be sliced dill pickles on the trays and plates, not sure about on the sandwiches.