delete 1 partition's OS and save other OS

No problem, take all the time you need. You'll work better if you're rested anyway.

One thing that can help and already has several times today is to take camera snaps of each tab in your BIOS so we can help you find the settings: Screenshots and Files - Upload and Post in Seven Forums - Windows 7 Forums

It's sometimes possible there's no way to disable the HD in which case you can first try deleting D so there's no partition to write the System flag onto during repairs. If it create one just to write it back there, then you can also create a logical partition where D was so that no boot files can go there anyway. We can give you the commands to create a Logical partition. I've already given you the commands to delete D.

Thanks for all the info.
got it done.
Razz.

Glad to hear it, Razz.

Can you tell us what worked for you exactly so it will help others?

When ready you can also mark the thread Solved.

I ended up using KillDisk , erasing all the partitions, reformatting into 2 disks(C and D) with Easeus partition wizard, reformatting each disk and reinstalling Win 7 on disk o OS "c" from an earlier copy through Active @ . Thanks again to Vista King, gregrocker and AddRam.

how can I give you guys a rep ?