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

root (hd1,0)1
chainloader  +1
I also tried
rootnoverify (hd1,0)
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
 <tab>root (hd1,0)
 <tab>map (hd1) (hd0)
 <tab>map (hd0) (hd1)
 <tab>chainloader +1
Obviously the <tab> should be replaced with an actual push of the tab button for the grub.conf.