definately a browser hijacker, dude...do aLL the above mentioned things, but first and most important is to BACK UP ALL YOUR DATA!!!!!!

there is at least a 50-50 chance a format/ reinstall is in your near future, so back up that data...

Yes ...as has been said , BACKUP....but be very careful restoring thing from a backup. It is possible to cause the same problem again yourself by accident. More than likely you will format real soon because stuff just will not seem right.
Good Luck

Thanks
Dudelive