Twilight Princess has to be one of my favourite three Zelda games. While I certainly can't argue that the game has an incredibly slow start, to me, almost everything that happens after that more than makes up for it. The game is vast in almost every way. The dungeons are huge, featuring many unique elements that make them fun to explore. Using the iron boots to walk along the magnetized ceiling to the fire dungeon, gliding over pits of spikes using the spinner to cling to the sides of walls, and whipping around the sky dungeon with the double claw shots are just some of the examples that come to mind. The bosses are also fairly gigantic, though a little on the easy side, and had several creative aspects and were quite memorable, like the fire giant who is first chained up when you enter his domain, or the giant fossil dragon whose attacks you dodge while using the spinner to climb higher and higher within the room, or the giant gohma that you must smash with the statues by controlling them with the divination rod. I'll never forget the silent beauty of snowboarding down a mountainside on a frozen leaf to reach a yeti's house that turns out to be a dungeon, or stepping into a derelict Temple of Time by means of a doorway that transports you into the past, or walking into Hyrule Castle at the end of the game and hearing the castle theme from A Link to the Past, except that it's presented in a much more eerie context.
Apparently I could go on and on about the experiences in this game that stuck with me. I own the Gamecube version, which may be easier to play over longer periods of time. It's unlikely that I would have stayed up the entire night to finish the game if I had to use a Wii Remote.