fbi virus, no internet in safe mode, can't start programs

so i have the fbi ransomware virus, don't know which variant, i can get into safe mode with networking but no connection, can't start any of my programs, can't boot from usb, i have win xp media, tried the xp malware removal instructions provided but i can't install and run anything, i tried kapersky, tried hitman pro but can't connect to the net so that didn't work, don't know what else to do, been trying this for about 15hrs so far, please i need help!, thanks., Larry