<< I've yet to play the new NASCAR game, but NFS5 beats down the rest of your list. >>
Every NFS title, including NFSPU, is an arcade game compared to GPL. GPL is still the one sim that comes very close to approximating the true driving experience of the actual type of race car that the sim is patterned after. And Nascar 4, even though it borrows the GPL "engine", doesn't quite compete in terms of realism. GPL will rule forever!
As for wheels, I'd second the Thomas', although for something more reasonable (ie. affordable), then it's definitely the Acts Lab. The Guillemot Ferrari (the same wheel is now also being sold under the Thrustmaster name, which was bought out by Guillemot) is OK as long as you get a newer unit which has the improved shifter paddles. The original revision's paddles were as delicate as butterfly wings. Finally, the Microsoft wheel is definitely something to avoid, unless they're giving them away. It's a CPU hog too.