Installing a custom Gingergread ROM (This will work for 2nd-Init GB Kernel ROM's as well)
-Go to Settings -> Applications -> and check the box next to "Unknown Sources" and then press OK on the warning that comes up. (this allows you to install non-market 3rd party apps on your phone)
-Put Droid 2 Bootstrapper and the ROM.zip file that you want to install on the root of your SD Card (main SD CARD directory, not in a folder)
-Install Droid 2 Bootstrapper
-Open Droid 2 Bootstrapper and select "Bootstrap Recovery"
-It will request Superuser Permission, allow it and then select "Reboot Recovery"
-Phone will reboot, use your volume buttons to move up and down in the menus and the camera button to select. Back button will move you to the previous menu.
-Wipe data/cache (always do when installing a new ROM)
-Then select install from zip
-Select zip from sdcard
-Select the ROM zip that you downloaded and it will install (about 10 mins)
-Once you reboot into the ROM proceed to setup your phone as you want.
you can use the DX bootstrap but you have to uncheck usb debugging.