Remove a physical drive from a simple storage space

Hi,

I have a storage pool with one SIMPLE (no mirror nor parity) storage space set up, which contains:

 -1x 2TB HDD

 -1x 250GB HDD

I want to remove the smaller 250GB hard drive from the storage pool, without loosing any data. There is enough space on the 2 TB HDD to store all data in the storage pool, hence a perfect solution would be, if the data on the 250GB drive is copied to the bigger one.

BTW I'm using WIN 8.1, so I do not have access to Server Manager, etc.

Thanks

Cornyfisch