First of all, when there are errors in CSS definitions browsers interpret them differently. That means that if in some browser you see what you wanted to do, it doesn't mean that your code is OK unless you test it in others.
I tested your code in IE5, Netscape 6.2 and Opera 6.0. Can you tell me what's wrong with Netscape? It does exactly what you told it to do. As IE and Opera did, with few comments.
I would like to recommend you to set the font properties correctly, by setting all attributes. Like this:
font { bold 14pt tahoma,arial,sans-serif; }
This will make it looks exactly the same in all browsers. This also allow you to remove [tt]larger[/tt]. Your definition [tt]font : bold larger;[/tt] seems to work as expected only in IE.
If you only set the background colour I'd change [tt]background : #F0F8FF;[/tt] to [tt]background-color: #F0F8FF;[/tt]
[tt]width : 20%;[/tt] is not recognized by IE5, and the width of table depends on text links in it (Netscape and Opera are OK).
I can't tell anything about [tt]position : fixed[/tt] because I don't have your environment to see what happens there.
I recommend you to check CSS part of GevGuru site:
Also read there what's written about [tt]position : fixed[/tt].
CSS sometimes looks like a game or puzzle, and the best way to learn it by my opinion is to follow cross-browser solutions only and test your code in different environments.
good luck.