Problem in viewing Gujarati ?

Open My Computer -> Control panel -> Fonts and check whether Arial Unicode MS fonts are installed in your computer.
It is not, then download it.

Apple Macintosh

You need to install language kits provided by Apple
Here are some links how to do that.

What is language Kit :: Apple :: http://docs.info.apple.com/article.html?artnum=60521
How to install Language Kit MAC OS 9::

Mac OS X Language Support Updates: Software Download
http://docs.info.apple.com/article.html?artnum=120063

Mac OS X 10.1: Viewing and Typing Text in Different Languages
http://docs.info.apple.com/article.html?artnum=106484
Fonts related Links
http://www.alanwood.net/unicode/fonts_macosx.html
http://www.alanwood.net/unicode/fonts_macosx.html#gujarati

Does your Web Browser Support Unicode?
Browsers

Apple Macintosh

Safari ( Default Browser of MAC) Supports Gujarati Language and No Special Settings are needed
Internet Explorer 5.2 (MAC) Doesn't have Unicode support for Gujarati Language
Others (PC)

Internet Explorer (version 6) if your internet explorer's version < 6 then please update is from Microsoft 's site.
Firefox 2.0