alven

my computer is an english system, 2000 windows. I can write and read in english, also I can write Chinese, surfing Chinese websites. But I just can't use QQ. I download QQ2006, install and run the procedure, I can write Chinese to my friends, and my friends' chatting to me are all ???? and wrong codes. and the same ,other programs I download just can't display with Chinese, but with ????and wrong codes. a week ago, a warm-heart man tell me use the control panel of my computer, and change the settings on regional options, and change language settings, but then computer shows there's a need to insert 3#disc. of 2000 system, I have no idea of how to do with it, cause I will maybe  get one.
my intention is that who can help me to solve this problem will be very appreciated.  

again with many thanks. specialists  

Alven  
17/01/07