For quite some time I used Microsoft Internet Explorer as my sole browser. I admit that v6.0 is much more capable and stabile than v4.0 and v5.0.
However, after studying web design, I learned that IE does not conform to the Web's universal standards (See for reference: http://www.w3.org/ )
I tried using two of IE's competitors, Opera and Mozilla.
Opera loads pages faster than IE, but it does display the wide variety of pages that IE does. For example, Opera cannot load www.macromedia.com.
Mozilla, which is a stripped down and less-buggy edition of Netscape, is now my browser of choice. It thoroughly complies with W3 Web standards. It is amazingly stabile; after weeks of use it has not crashed once. It is also at least as fast as IE, if not faster.
For further study, have a look at:
http://www.mozilla.org/
http://www.opera.com/