Yes,
 
Haven't thrown my XP discs away either, though likely won'r be using them again.
Funny thing is that you can throw all of them away and keep one.
The OS installation disc provided with a computer is the same disc provided with another computer.
It's only the OEM license number that is attached to a specific machine if the discs came with a commercial rig. Plug in the number for the specific computer and the same disc  works for all of them.