My Safari searches Bing instead of Google, +++

The other day I opened a website (evidently a fake link to a craigslist-like site) that asked me to install a new version of Flash. I downloaded the file, installed it, and that's when the problems began.

Lots of programs (Mac cleanup, etc.) began to run in the background. I went to Applications and many programs had been installed. I manually uninstalled them, but something is still going on wrong.

I get popup windows.

I noticed that my firewall was turned off (not sure if it was on before)

My Safari searches on Bing instead of Google, even though it's set to Google on Preferences