Help - I've changed something in Windows and now i cant put it back?

So, i deleted a few fonts, and now, even in my logon screen and etc, i have a font that isn't comprehensible. i tried to change it in Tweak.UI, it didnt work, i tried regedit, TuneUp Styler, the usual windows apperance, deleted the font, but it is still there. Can someone help me? My OS is Windows Xp Sp3.