First, you'll need to help us a bit more. The information you give is not enough to suggest anything.
"Then i cant get any pages to show." causes the most hassle. How do they not show? I suppose the browser opens, but then a message appears saying that the website is unavailable?
There is a good chance that you have been hit by a dialer, changing your dial-up number to an 09 number and when you connect it then lets you get nowhere on the net.
On most PC Advisor coverdiscs there should be Ad-Aware. Install this and search for malware - software that does nasty things to your computer against your wishes.