To Uninstall Ubuntu from a Windows 7 Dual Boot you will need a Windows Repair Disk or Installation Disk. If you don’t have a Windows Repair Disk or Installation Disk available, you can create one using a family or a friends Windows 7 computer.
To Remove GRUB:
1. Need a Windows Repair Disk or Installation Disk and boot from it. ( Click Here to make your computer boot from windows 7 Disk )
2. Once you boot from the installation or repair disk media. Click “Repair your computer”
3. Open the Command Prompt, then type: bootrec /fixboot and press enter, then type: bootrec /fixmbr and press enter.
4. Reboot to boot into Windows. Then follow the steps below to remove the Ubuntu partitions.
To delete the Ubuntu Partitions:
1. Go to Start, right click Computer, then select Manage. Then select Disk Management.
2. Right-click your Ubuntu partitions and “Delete” . Make sure you select the Ubuntu partition!
3. Then, right-click the partition that is on the Left of the free space. Select “Extend Volume”.