Here's another vote for the Lionel Pennsy set, which does go on sale fairly often it seems. It will be much cheaper than an MTH set. Another nice thing about this Lionel set as opposed to an MTH ready-to-run set is that the Lionel fits very neatly in a smaller box, with less packaging. I have both manufacturers' low-end boxed RTR sets and have to keep picking them up and moving them for my house cleaner. The Lionel is a snap to pack up or drop in the trunk to visit my mother at Xmas. As has been noted, the Lionel track will handle being setup and torn down better than the MTH track, if that's something you'll have to do. The MTH plastic guides used to connect the track can break off during setup/tear down. That said my floor layout is actually MTH because it comes in a smaller O-31 radius. But the Lionel 0-36 is still manageable size-wise if you go with the simple oval supplied in a RTR set.
Good luck!
Tomlinson Run Railroad
