Help Please with issue

I have a series 3 Tivo that started freezing, stuttering and rebooting. I had a 500GB HDD that had some recordings on it that I wanted to keep. I used WinMFS to copy to a 1TB drive. When it was completed the program asked if I would like to expand. I chose yes and I got a message that unable to extend. Not enough partitions. Is there anything that I can do to totally utilize the 1 TB drive space?? I don't want to lose the recordings on the old drive that was dying.



Any help would be appreciated.