Many things freeze well--the things that don't are really the exceptions. I'm not vegetarian though--don't know if it's trickier if you are.
I freeze soups, stews, chili, bbq beef and pork, quiche-in-a-bag (crustless quiche which you freeze unbaked and just pour in a pie plate and stick in the oven), roast chicken, meatloaf, meatballs, cooked ground beef, cooked beans, etc. Chicken frozen in a marinade can be dumped into a dish and baked and tastes wonderful.
I found that it wasn't a good idea to go by "cooking for the freezer" type cookbooks as I often made stuff my family wasn't nuts about. What worked better for us was to just try to freeze one batch of a family favorite, and try it after two weeks to see how it worked in the freezer.