To merely view Chinese on the WWW, if you use Mac System 8.5 or Windows 95, you only need two things:
If this doesn't work, you may need to set the font preferences. Locate your font preferences (in Netcsape 4, Edit: Preferences: Appearance: Font). Choose the appropriate Document Encoding (e.g., Traditional Chinese) from the pop-up menu, and set both a fixed and a proportional font from among those you have on your computer. (The idea's the same, though the menus different, if you are using Internet Explorer.) Then proceed as above.
It is important to realize that these options only allow viewing and not input. If you want to use even the simplest search capacity, or enter data in forms, or (of course) do any word-processing with Chinese, you will need more. Specifically:
If you have these two items, then you are probably set to proceed: just select the appropriate "Document Encoding" from the Options menu in Netscape (e.g., for the Confucian Etext Project, this would be "Traditional Chinese-Big 5").
If you need more instruction than that, please try this well-maintained site that has both a lot of expert information, and links to many other sources. For Macintosh-specific information, the best place to start is the Chinese on the Macintosh FAQ on the Net, currently maintained by John Delacour.