partition magic click here will let you merge all your partitions into one with out losing any data.
i have just seen your other posting though click here when you say 'want to remove all on xp home' do you want to format the hard drive and re install xp fresh and get one C drive? if so you will lose any data thats not backed up.
to do this you will need to use fdisk and have a windows xp cdrom. do you have a windows xp cdrom or just a restore to factory setting floppy disk? if you only have a floppy disc then deleting any hidden partitions on your hard drive with fdisk or partition magic etc will mean that you cannot re install windows again. be very careful here.
can you tell us your computer make and model no. please? may help a bit.
if you have an xp cdrom then your fine, download a windows 98SEoem bootdisk from click here (works ok with xp) and use this to run fdisk and delete and create new partitions then re install windows. click here click here