Problems with internet access for certain users

Three of us use Windows XP at home and we each have our own personal settings. From the outset we had problems connecting to the internet but through pure luck, we managed to resolve them and each of us have been able to access webpages through our own respective personal settings.

However, we were caught out by a nasty collection of viruses (sasser, netsky and others) which (I think) we have successfully removed. Unfortunately, since then, the internet can only be accessed through my personal settings page (I am the adminstrator) - although all of our individual icons/logins are available here also. The problem is that webpages cannot be accessed through the other two users personal settings pages.

I have checked the internet and network connection settings on each user and they all look ok to me. Any ideas would be much appreciated.

Thanks.