Booting from HDD instead of SDD (not the other way around)

hi everybody,

i recently bought a OCZ Vertex 3 SSD 60gb (though i think i should have gotten the vertex 2 as my mobo is SATA 2) and installed windows 7 professional 64bit on it. 2 days later i realize i left some important configurations on my original boot drive (Western Digital Caviar Blue 500gb)

game configurations, currently downloading/ unfinished torrents, seeding torrents, etc. were all there.

i need to know how to boot back from my WDC 500gb drive instead of my SSD.

i remember seeing the os boot list on bios when installed win 7 on a laptop drive for a ZBox that didnt come with a dvd drive.

just incase my motherboard is a ASUS P5N-T Deluxe (socket 775, nVidia 780i chipset)

i would really appreciate your help on this