Sorry this is so late, just thought I'd help if poss...
I run XP on main drive, RH8 on the slave. No grub installed just Bootmagic for Windows. Automatically detects a linux install on 2nd drive & adds it to it's boot list.
When I switch the system on, first screen is BootMagic's menu, basically
1 = Windows XP
2 = Redhat Linux
Simple as that. Press 2 & she boots straight into linux, by default she goes into XP after 30 secs, but that's totally configurable mate !!
Hope this is useful to ya....
ps: IF you've already put grub or lilo on your MBR, the command to clear it back to a normal M$ mbr is simply (from dos prompt):
It won't screw / empty the drive either, just boot straight into wyndoze as normal