I recently had a problem where I wanted an internal hdd grub4dos menu entry that would boot the system from it's internal hdd to Windows normally - just as if grub4dos was not installed.
I tried menu items like
chainloader /ntldr || chainloader /bootmgr
but this did not work on Win 7 systems (for example) where the bcd was on the first partition but the C: drive was the 2nd partition.
also, using find --set-root /bootmgr did not work on a system that had multiple partitions and multiple OS's installed.
Then it struck me that when grub4dos is installed, a copy of the original MBR is in the second sector of the hard disk.
So the solution was simple
title Normal Windows Boot rootnoverify (hd0) chainloader (hd0)1+1
The rootnoverify seems to be necessary in some cases. Without it, grub4dos would not boot XP successfully, however the same chainloader (hd0)1+1 command when executed from the grub4dos console worked fine! Adding rootnoverify to the menu entry seemed to fix the problem.
So, as long as grub4dos is installed on the boot drive (with the default backup MBR option), then this menu entry should work OK as hd0 will (should) always be the boot drive.
I had not seen this elsewhere, so I thought it might be useful to post it.
Of course, if you install grub4dos with a timeout option, you do get the opportunity to boot using this original MBR anyway, but this is only on first boot before the menu loads.