Computer Browser being slow?

alright, so I got this Windows 7 computer around a year ago, and it was awesome. The browser I started using was Google Chrome, and it was extremely fast, and I was very satisfied. However, my browser started doing this thing around 4 months after I got it- If I clicked on something while another page was loading, it would NEVER stop loading. It got to the point at which if I tried closing it and opening it again, it would feature a blank page and claim that it was loading, but no matter how long you left it there, it would keep on going. The only way to get the browser going again was to restart it. However, yesterday, I was watching some Inuyasha, when my computer unexpectedly died (I forgot to plug it in). Ever since then, my chrome REFUSED to start, no matter how many times I restarted, shut down, or logged off. A friend of mine told me to uninstall chrome and and install firefox instead. Somehow, I managed to do this, and at first, it seemed to be working nicely. But then, I tried watching some Inuyasha, only for it to lag AGAIN. I tried getting on my Deviantart, and it started lagging AGAIN. If I go on my email, or facebook, or anything that doesn't require flash, it works fine, but I can't watch veoh, and I can't get on my Deviantart without an excessive lag. Please tell me what I should do. (by the way, I have AVG free virus protection).