1. booted into 7:
Make sure your computer is set to see hidden and system files first.
Then copy bootmgr file from Vista partition root to 7 partiton root. Then copy the boot folder from Vista to 7, telling it to skip copying bcd and bcd.log when it asks.
2. Then do this command from an elevated command prompt:
bcdedit /export C:\boot\bcd
3. Now set the 7 partition as active.
4. Now you can reboot and the 7 partition will be controlling that. You can also now remove Vista from the bootmgr using either easybcd or typing msconfig in the start menu search box, then boot tab.
5. Vista partition can now be formatted or deleted.