For kids ages 4, 2 and 1, it may be a good idea for them to play with the push wooden trains, as Landsteiner mentions above, or get the battery operated like the one below (from Target). I'm sure a lot of us started this way, and as we got older and more interested in trains (if we did), we purchased more expensive and sophisticated items. The set below should be a good starter and isn't too expensive and comes with a remote.
