I was struggling recently in wiping and restoring my MBR on my 2.5″ HDD, as I previously have LINUX install and many other OS that I have tested before.
Then finally I screw up, and was not able to use the HDD for quite some time.
But today have the time, and I take out the DISK for further torturing 
Finally I found MBRWiz, a free tool that is offer by the generous author here : http://mirror.href.com/thestarman/asm/mbr/BootToolsRefs.htm
I hope someone who are facing the same problems would find this little piece of DOS software useful as well.