Michelle did you create an extra partition this time ?
If not while its still empty and you still have a few glitches to fix then, (yes I know its a pain but it will save you a lot of hassle in the future), then reinstall XP again and create a second partition.
When you start the installation theres an option to install to the existing partition or to delete the partition.
Select delete the partition, it will ask if you are sure and I think you have to press L to delete it.
The next screen will ask if you want to create a partition in the empty space, select the option to create, think its C and then you can set it t the size you want, with a 320 gig drive such as you had then you could have 50 or more gig as your primary partition, remember it wants it in MBs not GBs so for 50 gig you need to type 50000.
Once its created format and install XP to that partition as you did before.
Once it is running in XP properly go into Admin Tools/Disk Management and then you will see the remainder of your drive as unallocated, you need to format it before you can use it but you can do it from inside disk management
