Alright, are you using a program to try and access irc, or are you trying to access it from this website? If from this website does your computer have Java installed and up to date? etc.. etc.. more info please.
I am using the website and have unistalled and reinstalled Java it is at the most current one I believe. It asks me if I want to block unsafe data from java and I always click no.
Answer the question about browser/version asked by Mikel. A browser is what you use to view the internets, such as "internet explorer" or "firefox" the version is what it will tell you when you go to "about ***" such is ie8.0--- or firefox 3.6.16.
You could always try installing an irc client on you computer, so you do not have to use the website browser.