WIN 7 install crashed, stuck with Windows.old on XP

The problem is quite peculiar: I have this old machine running on XP (32bit) and recently I have been trying to install Win 7 on one of my disks while keeping the Xp- that dual OS story really got me going because I have loads of old stuff with Xp I really don't want to lose.
So I prepared this other physical disk I have, had it partitioned and prepared and made the bootable USB with Win 7 installation.
Win 7 install got to the part where it started expanding files or preparing the installation and at that time the installation just simply crashed and returned to the black screen forcing me to manually switch off the computer to boot the old XP.
I'm not really sure why this happened (I even tried different versions of Win 7), perhaps because Win xp I'm keeping is 32 bit and the new 7 installation I tried to set is 64, or the processor can't support Win7 64 bit (even though my Intel Core 2 duo E8200 @2.66 GHz is said to support 64 bit versions of OS), but this Win 7 install is no go for me.

But the real trouble is this: now this partition I tried to install Win 7 on (on a completely different HDD!!!) is loaded with Windows.old files (some 2+ GB) I can't seem to get rid of: they won't be deleted- I took ownership, I tried Unlocker, I ran in Safe mode, all I could possibly think of.
Then I came upon this MoveOnBoot program, marked all those Windows.old files and folders for deletion, and lo and behold- upon reboot- MY XP WOULDN'T START AT ALL!
To cut the story short, I managed to run "last good configuration" and my Xp is fine now but the conclusion I drew is that somehow those Windows.old files have tied with my real system files on XP system disk (which has, as I mentioned, nothing to do with the HDD I tried Win 7 installation on)
and deleting them jeopardized the Xp.
How could that be? How could the Windows.old files on a separate drive (and after not successful Win 7 installation, of all things) have anything to do with working system files of Xp on a different HDD?
And how could I get rid of them?

Please help...
First, to dual boot xp and win 7, xp has to be installed first, and then win 7, so that win7's boot manager will take over the dual booting.

here are some sites on dual booting that may help:

above is the google search page with lots of hits on this issue, I would read several threads and then see if your issue is covered.

I did, Elisabeth, I went through so many threads that my head hurts :)
And XP was there first, like my thread says, XP was already there and Win7 would not install.
I did follow all the instructions found out there, but to no avail.

Now the Windows.old folders would not delete (even though Win 7 installation was unsuccessful) and it's driving me mad...
open the windows old folder, is there anything in there that you need??

if not, take ownership of the folder and then you should be able to delete.

above has a nifty download to do this.


if xp won't boot, then you have to boot into the recovery console and do a fixboot or fixmbr below are some examples of how the boot.ini should look, since you deleted win 7 you also deleted the boot manager which was in play with both installed

above are recovery console commands, the second link is a little easier to read and you can click on each heading for more detailed explanations.
The few times I've tried installing more than one OS, I've had similar problems to this, namely that the second OS has assumed it can over right the first.

This is suggested to be the problem in your case, by the creation of the Windows.old file.

My experiences with Linux were all disasters, frankly. Dual BOOT only being one. But I did once install Vista and XP on different drives with a dual boot.

I managed it by temporarily altering the BOOT priority in my BIOS, making the DVD drive first, my blank drive second and my XP drive third.

I should also add that my wife's computer uses W7 and frankly I find it slow. I might also add that I suspect that M$ may be making things deliberately difficult for XP users. Another example, I connected my portable HD to my wife's machine, previously formatted, NTFS on my XP machine, last night, to do a back up for her. W7 decided the drive was faulty and tried to reformat it.

I had carefully rechecked the formatting before I connected it to my wife's machine. I don't accept there was any problem, other than the formatting was signed by XP.