Code Listing 5.1: Grub Output
root (hd0,0)
filesystem type unknown partition type 0x7

Error 17 : Cannot mount selected partition

Solution
This error is returned if the partition requested exists, but the filesystem type cannot be recognized by GRUB.
Be sure to check your root(x,y) settings in your grub.conf.
Also, if you are trying to boot Windows, make sure that your grub.conf file has the root (hdX,Y) (or rootnoverify (hdX,Y)) and chainloader (hdX,Y)+1 in it.