My laptop stopped connecting to internet.

Hello,
I have a Compaq laptop and have always used it as my main computer to connect to the internet . I connect through my PC with a wireless router ( both use Windows XP). On my laptop, I always connect to the internet through Internet explorer which then takes me to my homepage which is Yahoo. Now, it will not let me go into any web pages. The message says that that "IE cannot display the webpage". I've tried going to other pages and I get the same message. Here are a few things you should know that could possibly be the reason this is happening... My daughter failed to close out of the Internet one evening (laptop), and was not realized until 14 hours later!! I at that time, closed out, then did a virus scan using my Trend Micro Internet Security Pro and it found 15 cookies and deleted them, went onto one mapquest via the internet,then signed off the computer at that time. Later, when I started back up the laptop, the Trend IS says there was two errors...one being a problem with iInternet Explorer and the other said something about an Unauthorized change prevention. It asked if I wanted to fix these and I said yes. Now, I cannot get on to the internet. I ran another virus scan and it found 19 more cookies. The Wireless internet connection says that it is conncected to Netgear (router) and the signal is excellent. Also, I keep getting messages that Trend IS is turned off, but when I go to it, it says it's on. I have tried all that I know how, the laptop says that it is connected to the router, but can't get it to work I even went as far as doing a system restore to the day before the internet was left on all night. My PC works fine and the internet explorer is also (which is how I am doing this now). By the way, I use Broadband HighSpeed (Roadrunner) on my PC, and I am using an older version of Internet Explorer, but do not know what version. So, I am thinking that it is the Internet Explorer, maybe it is disabled or something? Please help, and talk in lamens terms for those of us who know a little about computers, but not a whole lot!! Thanks!!