plz plz plz help i'm so confused

Hey i'm new to this forum and have some serious problems. I recently learned that to get rid of the HOT_KISS dialer virus you need a program called hijack this, i have downloaded this file twice and it doesnt work on my computer, in facts its more like 20 times ive tried, missin files etc. Is there any other way i can get rid of the virus, it basically disconnects me from my ISP, connects to a premium rate porn number and charges the hell out of me, their is also a dial up networking connecting called XXXSERVER, ive deleted it numerous times from the system registery but it still comes back when i connect to the internet. My homepage has also changed to something like www.777search.com or something. plz help, i really dont know what to do, it charged me 70 bucks last month. I have windows 98, pentium 1 i think and AVG software which picked up other viruses i had but not this one. I cant put into words how much help i need.

Regards

Graham