I'm not the smartest guy on here for sure, but SBF means to flash an android software on your phone and going back to that version bone stock... If you go to the top of the " all things root" section there should be a sticky. That sticky will tell you how to root, deodex and unbrick your phone.. That will give you good directions on Sbf'ing, but basically you get a program like RSD you download the version you want to put on your phone and you open up rsd connect your phone via usb click a box. select the "android2.3.32.sbf" and watch it do its thing..
Careful flashing. From what i understand. If you flash the newest version, then flash a really old version.. or like 2.3.15 i think you can brick your phone.. hope this helps.. Someone else should step in and help ya if I'm innaccurate somewhere.