Just in case you need some help w/the steps;
Tutorial/Walkthrough for flashing an .sbf to Droid 2 (unrooting/factory restore) - xda-developers
This is important...get into bootloader:
8. You now need to put your phone in bootload mode. In order to do so, power down your phone. Slide open your keyboard, hold the "up" key (the arrow closest to the enter button), and power on your phone. You should come up with a black background and text with something along the line of d2.35 and usb okay.
Tutorial/Walkthrough for flashing an .sbf to Droid 2 (unrooting/factory restore) - xda-developers
This is important...get into bootloader:
8. You now need to put your phone in bootload mode. In order to do so, power down your phone. Slide open your keyboard, hold the "up" key (the arrow closest to the enter button), and power on your phone. You should come up with a black background and text with something along the line of d2.35 and usb okay.