Help! Had it set up to triple boot, but lost Win 7

#1
Okay, first off, I'm no geek, so please be patient with me
Here's the progression of the problem...

I had my Dell Optiplex 745 set up to triple boot to Win 7 Pro, XP Pro and Ubuntu (on 3 separate drives) using EasyBCD. For some reason XP quit booting, saying it was missing a file... long story short I finally had to reinstall XP on in its drive. I didn't think this would be a big deal...

After installation, I rebooted so I could do some work in Win 7, but instead I was faced with 2 boot choices: "Microsoft Windows XP professional" and "Windows XP on D:\" (the latter was the old installation?). Win 7 and Ubuntu are no longer choices.

I went back into XP to make sure the other drives were in tact and nothing was missing, everything appears to be there. Checked the bios and the drives were all fine and working. I scoured the bios and boot menu don't see any way to get back to Win 7; the machine insists on the New XP installation. I removed the XP drive and turned that SATA port off in bios to see if I could get it to boot from the Win 7 drive, but the problem persists.

Oh, and for some reason it won't boot to my Windows 7 repair disc; the boot order is correct, the lights come on and the drive spins, but it goes straight to the XP OS choices.

I re-downloaded EasyBCD to install it on XP (I originally used it in Win7), thinking I could just re-set up the triple (or even dual) boot and regain access that way, but when I try to install EasyBCD, it cancels the installation (it tries to instal, then says "installation cancelled").

Is there a way to install EasyBCD on XP?

Other ideas? I'm desperate to get back to Win 7...