My default font is all screwy! :(

[phadam]

Hi guys, Just last night i shut down my comp like normal. This morning all my default font is now some random font i downloaded off of dafont a while back. I have tried fixing this in my safari/firefox/and mac preferences but no luck. Any ideas?? I cant even read emails now bcuz of the font style. grrr! is there a reset that i can do?? anything?? thanks!