I go along with Matt. If the Casserole fits well, hang on to it. Get nice wheels now and you can eventually put them on any bike you may subsequently get at some point in the future.
I just saw, (it may have been in Velo News) a list of tires used for Paris Rubaix Paris. Many teams used tires that were 17-28 mm wide. I use a 28mm tire in the back and a 25mm tire in the front mounted on Velocity A23 rims. They sure are smooth.