unpartitioning a hard drive - help please

[oldmotherfoccer]

is there any foccer nearby that could please help me understand how to unpartition matts hard drive, at the moment one bit is full, but i cant work out how to move stuff over to the empty side- like all his i-tunes - as then when he goes to play them it cant find them - so i have obviously missed out a needed and simple (not for this foccer) process in it all.

i could bring it round to a foccers house, or probably do it with a bit of phone help

we are in kettering and its an acer pc

thanks