[Suka]

I am not 100% sure of all the differences but i do know that the Lite screen is significantly brighter and works better in different lighting conditions. Also, having held both consoles, the Lite feels a million miles ahead in terms of design and build. The normal DS feels cheap and badly thought out, the DS lite looks brilliant and feels quality in your hands.
As for games, i don't actually own one so i can't comment so much on that. My little sister has one and she has quite a few games but i can spend quite a few hours on brain training or Sonic and Mario at the Olympic Games.
I also agree with Rock about it being a bit of a novelty at first and you could lose interest in it after a while but my little sister has had hers for well over a year now and she loves it, still!