Windows XP recovery?


OK, so I intalled Windows 7 on my HP Pavilion Dv8000 laptop thinking it would be a great improvement over xp. Unfortunately, I found out that Windows 7 did not support my sound driver or my sound card. I wanted to downgrade back to my old OS (XP Media Center Edition 2005) and I found out that I lost my recovery disks or either that my Laptop did not include them. I found 4 partitions in my hard drive when I upgraded to Windows 7 and I am sure that one of the partitions includes my recovery.

How do I find it and boot from it?