HI, I am trying to erase an MBR off an old hard drive and then would like to erase another drive and write over it. I know there are a lot of programs out there but not sure if there is one that's best. I'm perfectly happy paying for a reliable program but if the best one is free I wont complain either.
diskpart then /cleanall on the pointed disk. Rewrites zero's to everything including the MBR. It's not secure, but it'll write over the MBR for you. I also use partedmagic or partition wizard for that.
I usually just overwrite the disks with zeroes followed by a random binary write and then zeroes again. I don't use anything made by someone else for something I'm trying to destroy.