mgb
That screen image data looks like something is wrong.
One of your disks may be faulty.
I suggest you remove the new disk you added and try another.
Also run a test on both disks before proceeding any further.
Boot up to the sme install CD in Rescue mode and run smartctl, refer
http://wiki.contribs.org/Monitor_Disk_Healthor boot up to the UBCD (Ultimate Boot CD) & run a test on both drives using the appropriate manufacturers drive diagnostic utility.
Search Google for UBCD