got dell insp/4100 xp running f/fox.
when connected to internet i found comuter would lock up altogether after a few commands. error was first infinite loop then bad blocks. time out etc etc. i restored/deleted progs put bad blocks aside and defrag etc etc but still the same. took it to a chop shop and they said forget it/ new hard drive. so, i then uninstalled firefox and all the errors vanished with it. i then reinstalled everything and now all is well. i wanted to share this as it may help others with similar issues