Vaguely controversial statement time! I far prefer Star Wars: Knights of the Old Republic 2 to KOTOR 1. I mean, BioWare's original Death Star laser blast into a rather bland Star Wars gaming scene is a classic for a reason, but KOTOR 2 - for all its flaws - showed sparkling glints of actual brilliance. Unfortunately, a lot of people skipped it due to BioWare's lack of involvement, bugginess, and an ending that sort of, well, didn't exist. But that was then, and now - as of today - KOTOR 2's finally on Steam. So I'm going to show you how to turn it into the game it should've been all along.
It's actually really, really easy. Simply go here to download KOTOR 2's restored content mod [edit - link updated to latest version], which - after three years of painstaking excavation work - is finally complete. Just drop that in KOTOR 2's Steam App folder and you should be good to go. Among other things, the infamous HK (as in, HK-47, the galaxy's most lovable human hater) Factory and the story's intended endings are back in. On top of that, the mod fixes "over 500" bugs, because Obsidian, basically.
And now, if you need a bit more nudging, I will (without spoilers) put it this way: KOTOR 2 uses KOTOR 1's formula to deconstruct Star Wars and tell a highly entertaining story in the process. While Star Wars as a whole trends toward sweeping battles between Obvious Good and Even More Obvious Evil, KOTOR 2 paints in impressively subtle shades of gray. It may not sound like much, but just wait until a certain someone questions your every choice all the time forever, regardless of alleged alignment. It's quite a ride.
So yes, go play it. Otherwise, I will make my most disapproving face at you. It'll look like this :(