Backing up in order to preserve deleted files

[Santa]

Hi

the other day I accidently deleted an Imovie9 sourcefile as well as a "DVD-file" created from Imovie9 - it's a catastrophy for me as 11 kids and 22 grown ups are waiting for me to send them this video ...

I think I have an Imovie8 sourcefile, so I might be able to reconstruct.
But before I try that I and just to 100% safe I wondered ...

... if I could unmount the harddrive (HD1) from my IMac (running leopard), hook HD1 up to my macbook (running leopard) together with another clean HD (HD2) install SuperDuper on the macbbok and use that to clone everything (every little bit) on the harddrive and then use some other recovery tool to find the Imovie9-file and perhaps the DVD-file. I could then experiment as much as I want on HD2.

At the same time I thought that perhaps I could upgrade from .5 TB to 2 TB in the same process.

Thanks a quazillion for your help !!!

Krgds
Santa