Vista Boot Manager

I have two 500GB HDDs. I have a C:, M: and D: drive (note: I have one drive partitioned so when I mess Vista up and have to reinstall no data gets lost).

My problem is that D: (which is its own drive) is the first drive in my BIOS (I have switched SATA ports and everything to no avail) therefore Vista puts the boot manager on D: instead of C: (C being my Vista partition).

I have successfully managed to transfer the boot manager from D: to C: however I can not delete bootmgr.sys and the "boot" folder from D: even though it is on C:. Due to D: being the first drive, the boot manager on it takes precedence when booting thus it boots using the D: drive boot manager and disallows me from deleting the files as they are in use when Vista starts.

If I remove my D: drive all works fine except that does not help as I then cannot delete the files as the HDD is not plugged in...

Does anyone have any suggestions regarding my 'little' problem?

The BIOS on my MB lets me assign which drive is first, does yours not have the option?

It automatically detects the drives, so I assume manually setting drive order is possible however I do not know how to do it.

My motherboard is in "My System Specs" if you have nothing else to do...

Load your BIOS and go into advanced bios features and the hard disc boot priority should be the first one listed hit enter then use the page up or page down buttons to select your drive then hit esc 2x then hit F10 to save and exit the bios. Then if you selected the right drive Vista should boot up if not just go back and select a different drive.