Need help with messed-up hard drives.


Hi, I'm writing in (almost) complete despair as I have some serious issues with my 3 hard drives.
Here's how I have them:

1 - 250gb - XP installation
2 - 500gb - 7 installation
3 - 1tb - just data.

I installed 7 first and then xp following a guide:

After several trials and errors, each of which got me even more nervous, here's what I'm left with:

1 - 250gb - XP installation - when I connect this hd to the pc, the boot screen shows 3 windows 7 installations to boot from, none of which work, of course. Win7 and XP discs can't fix anything as they don't find anything to fix.
2 - 500gb - 7 installation - doesn't boot, Win7 and XP discs can't fix anything as they don't find anything to fix.
3 - 1tb - just data. - after the first trial (when I could still boot to xp) the disc was unaccesible, it showed up under My Computer but couldn't open it, this disc had no OS and it is the most important to me as it holds very important information.

I don't mind reinstalling win7 or xp, but obvioulsy I would like to recover those installations as I spent almost 6 hours updating those OS's.

Any ideas/guides/tutorials?
My most sincere appreciation to all of you for reading and helping in any way you can.
Is this with all three drives connected at the same time, or are you booting from one OS with the other disconnected ?
Terry: I tried either way, but can't access them.

Mahmoud: It's a shame I didn't know about this before. Thank you for your reply and the information. Do you think there is a way to recover the 3rd disk? (the one with just information, no OS).

Thank you again.
I would recommend trying out TestDisk from CG Security. It's a very advanced program, but if anything can bring it back, it can.
First, try disconnecting the other HDDs before booting the W7 DVD and running "startup repair" three times with just the W7 HDD available.
When W7 boots unaided, reconnect the other HDDs and add an XP entry (auto).
Terry, Mahmoud:

Yesterday, after a couple of hours of fighting, I was able to recover everything. The Win 7 startup repair didn't do it, so I (reluctantly) ended up reinstalling that OS. From it, I was able to access the other 2 drives!
I still don't know exactly what I did or where it all went wrong, but at least I got all my information back.

Thank you very much for your help.