You need to supply more information:
When are the fonts overridden ? If when browsing, which browser ? If word processing, which program ? Other occassions ? Can you describe the symbols ?
Having problem with symbols overide my chinese fonts. i have had my computer restored but the problem still remain. i am not sure if it is relate to spyware problem or not. Because my XP Pro is running perfectly after i have installed a spywarekiller