Java Problem

Hi Guys

From the past many years i used to update Java manually without any problems. I updated it like after every few weeks. Since yesterday i have been getting this message from few websites

http://oi43.tinypic.com/2djxq47.jpg

Now when i update it manually i get this message

http://oi44.tinypic.com/mvrq5f.jpg

When i click on yes then nothing happens. When i click on view certificate then it says that this certificate cannot be verified.... and then i click on install certificate, it says installed and still nothing happens after clicking yes.

I selected do not ask again until next update is available from the first photo and now whenever i am saving or downloading anything from the internet it takes some time and this same line is mentioned below the box where it asks where to save the file.

I am using Win XP SP 2. What should i do?

Thanks