Let the reconstruct complete before making any other changes to the server hardware.  Then verify the status of the Virtual Disks and actual size.  If the reconstruct completed successfully then you would have roughly the size of the 250gb hard space added to the Virtual Disk.   At that point you can choose to live with the set up.  Or the safest way to get back to the original set up is back up all the Data and start over from the beginning and wipe the drives clean reinstall the OS and then apply your back up of the Data.  
I have a PE 2950 with a PERC 5/i integrated RAID controller which lost a hard drive.  I got a new drive from Dell and put it in, but it won't rebuild.  It just says "Ready".  I have tried making it a hot spare, but it still doesn't rebuild into the RAID.  The logs only show the drive removed and replaced.  What do I need to do to get the RAID back to full capacity and use this drive? Thanks, Michael
PE 2950 Drive replacement