Problem w/ win98,ie55,w2kserver,wingate

I currently have a mixed environment of Win98, WinNT wks4 and Win95; the server is Win2k server w/wingate as proxy for the internet service. Processor clocks vary from 166 to 500MHz intel and amd?s processors. This week i updated four machines w/Duron850 and Athlon 900 w/M-812 Boards and 128RAM. I setup the same Win98 as the old machines and Office2k. At this moment, i don?t know why some Hotmail features don?t work and a lot of other web pages as they do good in other machines w/the same software. This is driving me crazy and my boss too. Please help me.