Same as yours, motorola droid 2, version 2.2.
Uh oh.
Don't use ROM manager then, it won't work. The D2/D2G both have locked down bootloaders. Because of this, CyanogenMod is still a work-in-progress and isn't recommended for daily use.
First off, back up everything you need. Contacts, apps, all that.
What you're going to want to do is download the
Droid 2 Bootstrapper and install it to your device, download
any ROM for the D2 from this website, CyanogenMod is listed here too, put it on the sdcard of your phone. Then, open Droid 2 Bootstrapper and hit "Bootstrap Recovery" and "Reboot Recovery".
You'll be in ClockworkMod now, so navigate (using the volume buttons to move, camera button to go forward and the power button to go backward) to "Wipe Data/Factory Reset", after that gets done then navigate to "install zip from sdcard", hit "choose zip from sdcard", find the ZIP file for the ROM you downloaded onto your sdcard and choose it, select "yes" out of all the "no"'s, then let it do it's work. Once it's done, reboot your phone (hit power until you get to the main menu, then there should be a reboot option there).
Note, if you do install CyanogenMod, don't install Droid 2 Bootstrapper. If you need to get into ClockworkMod, hold down Power, go to "Restart" and you should see "Reboot Recovery".