First and most important advice - do not do anything in terms of writing to that disk until you know you have the data off of it (and backed up). Do NOT continue with the Compaq restore process. Keep that disk safe!

Then (using whatever computer you can access), download Partition Find & Mount from here:
http://findandmount.com/

This is an ace little Windows utility that does a good job of passively finding deleted partitions. The less overwriting you've done the more data it will find. The joy is, the demo version is fully operational and you'll know whether it has saved your stuff or not. If your stuff is there it will present it in the regular Windows Explorer fashion. You can even copy files off the demo mounted partitions at a painfully slow rate so you can rescue essential items for free if you have the time. If you see gigabytes of your art history is safe, believe me you will find the forty four bucks for the full version that permits regular speed copying and rewards those programmers.

I know this works because it rescued me a couple of weeks ago. The disk I had was partitioned into C: and D: , the idea being that I could reinstall Windows without affecting my data on the D:. Trouble was, my WinXP disk is from before the service packs so it didn't recognise the large hard drive size. I'd created my first partition, formatted it and installed Windows before I realised the implications. That's when I discovered by backup was kaput!

Luckily I stopped there and started researching. After a few cruddy programs I found this gem and it recovered my D: drive. All was safe on that, but the old C: drive was toast (it could see it but it was too corrupt). I quickly purchased the full version and grabbed my stuff.

The program works fine with the hard drive placed in one of those outboard USB caddies and seen in Windows as a removable drive. Hitching it up to a spare SATA/IDE channel of another PC is quicker.

Even if that prog or others can't see your old partitions or data, don't give up on it. Keep that disk safe and use another (beg, borrow or steal) to reinstall Windows. Some other technology might save the day.