Hey no problem, f8 always works
. I know some mobo's have a boot option under f8 too.
going on the assumption that your running XP, insert your instal disk and boot from the cd near the beginning of the installer you will get the option to boot into recovery consle. Option C i believe. enter this and re-edit your configsys file through recovery console.
Remember, windows is a big gaping vagina waiting to get screwed over by someone. Way too many security issues. But we all use it anyways. lol