Windows 7: Removing Vista in a Dual Boot with Windows 7

I have Vista on a separate disk from Windows 7. Windows 7 is on one of my partitions on the disk. I tried to format the disk with vista by going in to My Computer, and right clicking on the disk and formating it like that, but it says that Windows was unable to complete the format. I unchecked quick format and put the allocation to default instead of 4096 bytes.
I'm doing it this way because when I go to disk management, it keeps loading, but nothing is shown. I have had it open for a long time now, and still nothing is showing. All it says is "Loading disk configuration." When I close Disk Management and open it again, it stays at "Connection to Virtual Disk Service."
Virtual Disk Service is set to start manually, and it is started.
Is there any other way I can format the disk, or do I have to do it this way. I still want Disk Management to work though.



EDIT:I did some searching and I found out what the allocation unit size is. Is it better for me to decrease the allocation unit size if I'm using the disk as a backup?

Download and burn free Partition Wizard bootable CD, boot it, select 1 for screen res, rightclick Windows 7, Modify>Set to Active, OK.

Now rightclick Vista to Delete, OK., Apply all steps.

Set Windows 7 as first HD to boot (after DVD) in BIOS setup.

Next boot the Windows 7 DVD Repair console or Repair CD, click through to Recovery Tools list to run Startup Repair up to 3 separate times with reboots to write the MBR to Windows 7.

If Disk Management will still not open, run sfc /scannow as Admin. If this fails, then run a Repair Install

Thanks a lot for the help. After using startup repair, it worked for awhile then after restarting again, I was told bootmgr was missing or something I forget. Then I removed the cable from the disk that I had just formatted, and used Startup Repair again. Now I'm going to connect the cable again and see if it still works.

Did you copy the boot files to the Windows 7 HD.

Nope. I don't even have them in my Windows 7 partition right now. I have the hidden files showing.

EDIT:I forgot to say that my Disk Management works now.

Please post back a screenshot of your full Disk Management drive map and listings, using Snipping Tool in Start Menu.

Is it starting correctly now? With or without Vista HD?

It isn't working now that I put the backup HDD back in, the vista one. It just stops at "Loading disk configuration information..."

I'm not sure what allocation unit size I should set the backup disk to. Should I reformat it again so that it is at the smallest size? Or should I leave it as 4096 bytes?

Without seeing a screenshot we can't be certain what is causing the problem.

Since I believe you used Partition Wizard CD to delete Vista and mark Windows 7 active, boot back into it and make sure Windows 7 HD is marked "System Active Boot," then rightclick Vista HD to Wipe partition with one set of zeros to make sure it's clean.

Then you can rightclick Vista to Create a new partition of full size to start (if that's what you want), format Logical and label "Data" or such.

If Windows 7 is not marked "System Active Boot' then check any other partitions present to see if they have those designations. Then rightclick Windows 7, select Modify>Set to Active, OK, Apply all steps.

Finally boot the Windows 7 DVD Repair console or Repair CD, click through to Recovery Tools list to run Startup Repair up to 3 separate times with reboots to correctly recover the MBR into Windows 7 partition only.