Viruses, pop-ups, windows is all bodgificated!

Hi there, I recently downloaded a game off the internet and have received many irritating errors. Firstly, AVG windows keep appearing with threat messages, some of which I could not heal, and many virus have been found.
I did an Adware scan with Ad-aware SE personal and scanned for spyware with Windows defender and Sunbelt counterspy. After removing all visible threats and the game, I am still receiving the same symptoms, annoying and indecent pop-ups on sites like google, viruses, etc.
I recently heard of something called Malware... Could it be this?
Please help, appreciated ~Fishy25

HijackThis
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