While browsing Microsoft's web site, I ran across the following warning regarding the use of Internet Explorer 5 with Visual Studio 6:
"The Design View editor of Visual InterDev 6.0 is currently incompatible with Compatibility Mode, and may not function correctly."
(http://msdn.microsoft.com/vstudio/technical/ie5.asp)
I think I'll stick with incompatibility mode. At least that way I won't be disappointed.