If you want to uninstall the windows vista operation system, then you wouldn’t be happy to know that there is no uninstalling option for Windows Vista. Yes, the Windows Vista installation is permanent. You cannot uninstall windows Vista from Add/Remove Programs. In case of dual boot, most importantly you will have to restore the MBR to what it was before installing Windows Vista. Like in my case, I have windows XP installed on my Desktop PC and I install this Beta Trial version of Windows Vista.
(Windows Vista uses different mechanism to boot the system. Earlier OS have been using NLTDR but in the case of Windows Vista it is BOOTMGR.)
In any case, if you want to remove the Windows vista from dual boot system, follow the following steps I Performed for the same. Remember it is not a task for faint hearted.
Given below are the steps I performed to remove the Windows Vista from my PC.
- Boot the computer in to Windows XP.
- Insert the Windows Vista DVD in the DVD Drive.
- Go to "Start" and "Run". Type in "d:\boot\bootsect.exe /nt52 ALL /force" (without quotes, d: is the DVD drive letter.).
- Restart the computer, and you will notice the boot selection menu is gone.
- Format the partition/drive where you had Vista installed.
- Remove two files (Boot.BAK & Bootsect.BAK) on XP root folder (C

Note. Bootsect.exe is a utility by Microsoft which updates the master boot code for hard disk partitions in order to switch between BOOT MGR and NTLDR. You can use this tool to restore the boot sector on your computer.
You can type "
bootsect /help" for more detailed explanation of usage.
Performing the above step helps in returning to the previous state, when I didn’t installed the Windows Vista.