Ghost 15 to replace a 100GB HD to a 320GB HD

Computer restored good but only shows 100GB (there is another 205GB unallocated). How do I easily and safely show the full 320GBs? I had mistakenly not clicked on Resize drive after recovery and now dont seem to have that option if I am to restore once again. Note: I have two partitions and am running Windows 7 - 1) 100MB System Reserved 2) 93.1 GB NFTS C: and 205GB Unallocated

 

While I am sure this is easy, I just can't risk messing it up!

 

Thanks!
Brian