The problem:

I have a separate drive for windows and linux. Grub was struggling to boot windows i would get

"file system type uknown, parition type 0x7"

I got this error using a grub config of

chainloader  +1

I also tried

chainloader +1

This setup would just hang and eventually prompt for a Ctrl Alt Del

The Solution:

To keep windows happy this setup seems to work fine for me in grub.conf. hd0,0 is my linux drive and hd1,0 is the windows drive.

title The Windoes
  root (hd1,0)
  map (hd1) (hd0)
  (hd0) (hd1)
  chainloader +1