install XP on 400gb SATA drive

i want to do a clean install on my 400gb SATA drive but when i do it, of
course it only shows 137 gb available. how do i fix this? i want all my gigs
cause it really bugs me to have programs and stuff installed on 2 drives as i
had before...

BACKGROUND

k so my 120 gb hd was filling up so i decided to get a cheap but highly
rated 400gb wd sata drive. i cloned my boot drive and everything booted (old
drive no longer plugged in) and everything worked fine. the thing is, some
programs got corrupted and every file (like word docs for ex) have the
generic icon that is given to a file with no known supported program. so im
thinkin, 'screw it, i'll do a clean install.' and heres where im at...ive
searched and searched and have found nothing that can help me. the way my
comp was before was that i had programs installed on a separate drive from my
c: drive. long story short, it created to many generic icons and im just anal
with organization and i want everything to be on one drive. the only thing i
want on any other drive are my editing projects.