You can format a partition using either the Disk Management Console or you can use the Windows Vista DVD to achieve the same result.
To use the Vista DVD proceed as follows:
1/ Switch on your PC
2/ Quickly insert the Vista DVD into your CD/DVD-ROM drive
3/ A message will appear asking you to 'Press any key to boot from CD/DVD
4/ Press any key
5/ A black screen will now appear with a progress bar along the bottom. The legend say's 'Windows is loading files'
6/ After the files have been loaded the Language screen will appear.
7/ Select your language from the list and press Next
8/ At the Installation screen press the Install Now button
9/ The product key window will now open
10/ Type your product key number into the available box and then press OK
11/ The End user Licence Agreement now appears. You 'must' accept this to continue
12/ The next screen to appear is 'Where do you want to install Windows'
13/ At the bottom of this window you will see an option marked Drive options (Advanced), click on this option
14/ In this Window select the partition you wish to Format from the list available and then click Format option link
15/ A message will now appear informing you that all data will be destroyed. Click OK to proceed