I has a problem with my partition table hard disk.

Hi!:

Last week I try create a new partition in my hard disk for intall Linux. My disk have 9.89 GB. And was install Win200 in it. I used Partion Magic Soft to adjust the space and create two partitions one with 7.35 GB and other the rest. Ok?
But when I reboot, my COMPACT asked me if I want update or restore de MBR, and I answered incorrectly because I said "restore".
Now I have only one partition, but Win2000 use only the first 7.35 GB, the rest is unknown for FDISK and Disk Manager of Win2000 and Partitional Magic. In Win2000 now everything is Ok.
What can I do for restore this part?
If I delete the current partition and create, for example:

1) 7.5 GB (active) "Observe that is great that 7.35 GB the current size".
2) the rest.

Win2000 start correctly? Is my question.

Thank in advance!

Julián.