I'm seeing almost the exact same problem on a Windows 98SE system:
AppName: iexplore.exe
AppVer: 6.0.2800.1106
ModName: msvcrt.dll
ModVer: 6.1.8293.0
Offset: 00015ca2
It doesn't happen all the time but is pretty consistent at certain sites. In particular with NetZero's webmail.
We've applied Windows Updates. We've had IE6SP1 setup reinstall modules. We've run updated Ad-Aware, SpyBot S&D and McAfee Virus Scanner.
For the moment I've installed Firefox so they can get their mail. Hopefully they'll decided to stick with Firefox but I'm still trying to find a solution.