Space Mountain - WDW. DL has nicer rockets, but the track itself is kind of bland. Throw in the post-ride thing at WDW, and WDW wins.
Haunted Mansion - WDW by an exceedingly tiny margin. WDW has the edge of two extra rooms (though most of the library ends up in the queue at DL anyway), but DL wins on exterior.
Pirates of the Caribbean - DL. The ride is twice as long. WDW has a better queue, which makes up for some of the extra length at DL, but you'd be crazy to vote WDW's over DL's.
Star Tours - WDW. Haven't been to DL's updated version, but WDW has better capacity.
Castles - Tie. WDW's is bigger, which is neat, but DL's is smaller, which is also good. You don't have to see a castle from Tomorrowland.
it's a small world - DL. Look at the exterior.
Big Thunder Mountain - I don't remember DL's well enough to choose either way.
Splash Mountain - I don't like water rides, so I haven't been on WDW's in a long time.
BONUS:
Tower of Terror - WDW. It's more or less Pirates of the Caribbean all over again, but backwards. DL's is an imitation with half of the ride missing.
Soarin' - DL. Nicer queue and shorter wait.
Toy Story Midway Mania - DL. The queue isn't as pretty, but you're not in it for as long.