My PC won't start!

Hello, I am not able to log in my laptop since a few days, the last moment I was working on it, I was downloading a game from gametop.com and meanwhile I was downloading an antivirus for my pc, when the game was fully installed I opened a new web page but it was not my homepage (google) instead it was a Japanese or Chinese web page. I tried to open google by changing the URL but just the minute I changed the URL to switch the page my laptop just got "not responding" and was just freezed I tried to restart and log out but I was not able to do so even by using shortcut keys and I forcely pressed the switch off key and my laptop got shut down. When I again tried to start it I was not able to log in even though I entered the right password and it again got freezed.

I am having windows 8