Windows 7: reinstalling win xp on dell inspiron 630m

my friend has Dell inspiron 630m, which didnt come with OEM Win XP CD,

i believe it contains hidden system partition with original XP on it

how can i reinstall winxp from system drive

the laptop has Win XP Product key or serial number printed on the back of laptop

Is CTRL+F11 on powering on still working?

The Dell-specific Ctrl+F11 process is supposed to completely automate the restoration process, returning the hard disk to the state it was in when Dell shipped the computer. However, overwriting the MBR by using a boot manager, using the commands "fixmbr" or "fdisk /mbr", installing from a Windows installation CD, and assorted other tasks a user might do will inadvertantly break Ctrl+F11, rendering the system unable to boot the DSR partition. Furthermore, changing the partitioning by adding, deleting, or resizing partitions will cause DSRcheck to fail, so even if Ctrl+F11 works, the restore process will abort without attempting to restore the Ghost image

If Dell Recovery won't run as specified above then you'll need to find an XP installer for your licensed version on the web. It also needs to be OEM sku, meaning it cannot be a retail installer but needs to be OEM.

If you end up looking on torrent sites for this disk be sure to read the comments to see that nothing is added like a crack since you have a Product Key to legally activate it.

please report back if CTRL+F11 is working.
If not.... Inside the Dell PC Restore Partition or
Inside the Dell PC-Restore Partition