[AntiGrav82]

I would first like to say that I am new to the XBMC community. I just recently purchased an original Xbox console that I would like to mod with XBMC, perhaps a bigger hard drive. I was wondering if XBMC upconverts Xbox games to HD. Do Xbox games look smoother?

[Lucleonhart]

Well, XBMC is a mediacenter for movies, music and such things. It will not enhance your normal XBOX games though.
XBMC does not support the original XBOX anymore, maybe you want to take a look at the http://www.xbmc4xbox.org/ website for infos about xbmc for your xbox.