Acronis TrueImage is the way to go. I've used it and it's awesome. I replaced the 80gig C drive that came with my HP with a 160 gig WD. I had no XP disc so I felt this was my only option.

After all said and done, everything was exactly as it was before. I was amazed and totally thrilled after fretting over it for some time.

I Highly recommend Acronis

Edit: As far as externals go, I bought a 60gig portable only for the sake of backing up or cloning my C drive. Thats the Only thing on it and I don't use it for anything else. They're dirt cheap, so why not. I wouldn't dare back it up to any of my other externals that I use for media.

1 - 1 TB Free Agent Seagate
1 - 1.5 TB Free Agent Seagate
1 - 2 TB Free Agent Seagate

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