Internet /Modem problems

Whilst on the net my modem keeps stopping to negociate a connection. I am still connected to the net @ 28800 and it just HANGS and does nothing.I can’t identify the source of the problem.I am running a Pentium11 266mhz, 128mb Ram,Win98,Outlook Express 6, Internet Explorer 6,Innoculate It,and DU meter.I have changed virtual memory to manual Min 130 Max 430.I also set my pc to network server.My modem is motorola 56K speakerphone. I have latest drivers from motorola.It is set at max speed 115200.Ihave 20g h/d,only used 6g.
I reguarly do cleanup, scandisc and defrag [weekly].Any help would be greatly appreciated as i am fairly new to pc’s. If you need any more info just ask please as this is driving me up the wall.