Java not working, tried many things, please help!!!

Hello, I hope someone can help me please.

I have a windows XP SP2 laptop with IE version 6.0.2900.

Suddenly 3 days ago two websites that I was using stopped working. I saw a Red X on one and the other website said Java was not working on my computer. I googled the problem and have tried about eveything including removing and reinstalling Java several times (both online and offline). There were no apparent problems, with activation in IE,
One of the websites is this one. I cannot see the chart, only a red X
http://www.netdania.com/Products/li...ates/real-time-forex-charts/FinanceChart.aspx

Then even the Java installation stopped working. If I try installing online it says "uncompression of downloaded file failed" and quits. If I try the offline version it says "This software is already installed (even when it is uninstalled). Do you want to reinstall it?" If I say yes, it says "This action is only valid for products that are currently installed."

Finally I downloaded an older java version 5 update 15 from oldversion.com and installed it. But now even my trading software that was working (even when Java was not ) does not work. It says "windows cannot find javaw.exe".

I have the following software: Avg antivirus 8, PC tools firewall plus, Comodo BO clean 4.27, Spyware blaster, Spybot S&D. It is possible that these problems may have started after updating any one of these softwares which I do about everyweek or so.

Please help somebody. I could install Firefox I suppose and see if that works, but my Trading software is also not working now because it cannot detect java, which is my main problem.