Since it was unreadable it looks like you had a disc problem. While chkdsk may have corrected some sectors, at least enough to read, it doesn't necessarily mean it corrected them all. Some of your data may still be corrupted or simply lost in chkdsk repairing the disc. Actually, it might not have even been there if it didn't save correctly to begin with.
I can't tell from your post whether you did a backup to this disc before your old computer crashed or if you recently did a backup of the "new" computer and your looking for that. It might be that the disc is readable but still bad and your data is being corrupted when written.
I would expect the slave drive in the new computer to have these drive letters and that the C drive is the current hdd and D drive the cd drive, leaving the next numbers for local drives as E and F.
If you can see the other folders under these drives that were present in the old computer, I don't see why documents and settings shouldn't be present. However, it may be that this folder is user specific in windows. XP allows multiple users to use the same computer, so it assigns this folder to different users. Once you move the hdd it is no longer running windows XP so user specific folders may not be visible as you would normally expect when the OS is running.
What you may want to do is search for that "user" folder (whatever you called yourself in the old computer) and then see if the doc/set folder is contained in it. You could also swap the drives, that is make the E and F drives master and the current C drive slave. Boot to the E drive, have windows XP sp1 load, and see if you can find the documents and settings folder that way.