1. Log into Windows
2. Click Windows menu, hold shift and left click to restart Windows into Advanced Options menu
3. Choose Troubleshoot > Advanced Options > Command Prompt, wait for the reboot
4. After reboot, reselect Windows
5. In Command Prompt, type bootrec /fixmbr and bootrec /fixboot. Then close the Command Prompt and choose Continue to continue login to Windows
6. After logging into Windows, run diskmgmt to remove the volumes from Ubuntu

You can also use GUI solution like EasyBCD to remove the Ubuntu boot item from Windows Boot Manager.