The boot manager has changed in Windows 7 (and maybe in some Windows Vista installs.) Instead of editing boot.ini, you have to use the bcdedit.exe utility.

To see the current configuration, launch a command line and run bcdedit with no arguments.

When you do that, you'll see each entry listed with an identifier, the simplest will probably be {current} and others will be long ids, like: {ac94140f-ef16-11dd-95f1-80da9636166b}

To backup, assuming you have a \bcdbackup directory:
bcdedit /export \bcdbackup\BCDBackup.bcd

To change a label:
bcdedit /set {current} Description "Windows 7 x64 RC1"