Look on the Properties box of your active Windows 7 User folders (Documents, Pictures, etc) for each one's Location
. If necessary on the Location tab you can Restore Default
In the above screenshots, it shows the location where I have moved my User folders. If I Restore Default
, it will change back to C:\Users\Administrator\Downloads.
You delete an OS by backing up everything you want from it, then deleting it's partition in Disk Management.
There is a possibility that you have boot-critical files for Windows 7 on the XP partition, which is one reason why we need to see the full Disk Management screenshot with listings - use Snipping Tool in Start Menu.