Those commands are for XP only. You will need to follow this to fix a Vista boot loader.
Repairing the Windows Vista Bootloader - NeoSmart Technologies Wiki
Repairing the Windows Vista Bootloader - NeoSmart Technologies Wiki
Alright clarify for me what you are trying to do. What is the 2nd installed OS? Win7? Vista? XP? Linux? Just saying 2nd installed OS doesnt mean anything as it can be any OS out there which was installed 2nd. I dont know which order you installed the OS's in so just saying the 2nd installed one gets us no where.
Plus if you only have XP/Win7 and you are trying to remove Win7 but still keep the BIOS Boot Method my next question would be why? If you remove 1 of 2 OS's installed then there is no need for the BIOS boot method or a Boot Selector screen. It would just go from the BIOS splash screen right to your XP install. No extra steps needed.
So clarify for me what you have and what you want to do. I know you have XP on your 1st HDD 1st partition. Win7 on the 2nd HDD 1st partition.
Which one do you want to keep which one do you want to remove? Are you going to install Vista/Win7 again or just stick with a single boot?
I will need to see a screen shot of you Disk Management screen. Start>Right click on Computer>manage. When that window pops up select Disk Management.
Upload it to Imageshack.us or Photobucket and then paste the forum code in your response.
I will then be able to determine if XP or Vista has the boot priority. From there i can advise you better.
Well this will be tricky.