Security issues with Hotbar/Gator

Alot of my user’s have installed a free software called Hotbar or Gator including myself. I started to notice that I was getting alot of pop up ads all of a sudden and alot of junk email. I have now uninstalled hotbar and downloaded a free ad aware program that delete’s all the ad junk on your computer. Now my computer has no pop up’s and no junk email as of yet. Are there any risk’s if other user’s want to keep hotbar on there systems? As far as security, what type of information can people get from your computer? Does this lead to back doors into your system? Very concerned!

Thanks!