Solutions to errors » Computer Problem? You Must Answer Please?

I’m using a Inspiron 2200 Dell Laptop with Windows XP. I have a problem with logging-in to many websites. For example, http://www.youtube.com When i hit the sign-in button my computers take me right back to homepage? What’s wrong with my computer? It also does this same problem with some other websites like http://www.break.com/ I can’t install silverlight either!! When i go to my add or remove programs thing, it says that i still have it installed on my computer which i believe is silverlight 1.0 and the newest is 3.0. So i am lead to believe that i have it installed but, whenever i go to websites that require silverlight to be installed, it says i need to install it! When i try to install it, it’s just an upgrade for what they believe is installed on my computer but isn’t! So it tries to upgrade 1.0(which i don’t have) to 3.0, but when it tries to upgrade it, it says that it can’t find the silver light 1.0 and it wants me to locate it (which i can’t) What is this problem? Whenever i go to a page on http://www.mediafire.com/ A big screen appears and says there was a javascript error in the process and i should try a different browser(i currently use ie8) I switched to firefox just to see if it made a difference and it didn’t, now i’m back to ie8. How can i fix these errors? Please post a very descriptive post about how to fix these problems. Hint – I don’t know if this is right but, Javascript error might be the cause of the log-in problem, and the silverlight problem might have been caused by an unsuccessful uninstallation/installation? PLEASE POST ANY HELP BEST GETS 10 POINTS.
- Thanks very much for all help provided!