I would advise playing through the first one again anyway. It's possible your computer just, well, crashed, or you needed a re-install, or whatever.
Another reason for this is due to the fact that KotOR 2's plot, while not nessecarily incredibly confusing, IS quite hard to follow, and a lot of the more major elements of the game would be lost on you and/or make no sense, due to the fact that you have not played the first game.
A final reason to wait is that there is a LOT of content that was cut out of KotOR II, which makes the experience much less than desirable and takes away from a lot of the original artistic intent. There is a patch coming out to put all of this cut content back in, and playing your first time through with the added content, well, added, would ultimatley provide you with a MUCH sounder and more enjoyable game experience.
That's great, but we already have a KOTOR2 thread.
http://www.killermovies.com/forums/showthread.php?s=&threadid=316496&highlight=kotor
Closing 🙂