A good first step would be to re-write it and use html, you know, things like h1, h2, h3, p, perhaps a few ul, li and the like.
You site is almost totally lacking in html tags, apart from the div tag, link tags and img tags - there isn't even the standard beginners favourite tags (<br> and ). It is all plain body text, the least used and also the least useful thing on a web page.
You could also try a css reset (although with the distinct lack of html, I'm not sure if it will improve things much, but you should have a reset anyway) so try adding margin:0; padding:0; to your body's css.
But until you do that, it will be tricky to give much advice.
this is the most extreme case of divititis I've ever seen. ;)
PS how do you imagine people will feel when you tell them to update their browser? Pleased? Or annoyed that you are insulting them. Especially as you give the same message to IE9, IE8 and IE7 users, and all of these are still supported...
In fact one hasn't even been released yet (IE9). I'm not interested in your anti-MS propaganda and anti-MS attitude, I don't like it and yet I don't even use IE (I use firefox). So how would someone who liked IE8, or IE9 feel - would they stay on your site, or would they go???
Remember, you build web sites for users, not to suit your own browser / OS / whatever
And you are risking annoying around 50% of your possible viewers - can you afford to do that?
@drjohn : I said just on Internet Explorer 6 not on 7,8 or 9, on them my web is working perfectly fine. I just want to have suggestions or any mutual solution for ie6. I dont think that 50% population is using ie6. Its not against MS, I myself use IE 8.