I would assume your best bet is to go with a Microsoft product on this one. The last compatible Internet Explorer release seems to be 35.01.
OldApps has a realy nice list of latest released versions for the given platforms. They also provide aHowever, contrary to that table, download5.01 is listed for Windows 3.1 as well.
Operating System Latest Software Version
Windows 3.1 Internet Explorer 3.01 (Windows 3.1)
Windows 95 Internet Explorer 5.0
Windows 98 Internet Explorer 6.0 (Setup Only)
Windows 2000 Internet Explorer 6.0 (Setup Only)
Windows ME Internet Explorer 6.0 (Setup Only)
Windows Server 2003 x64 Internet Explorer 7.0 (x64)
Windows Server 2003 Internet Explorer 7.0 (Final)
Windows XP x64 Internet Explorer 8.0 (XP x64)
Windows XP Internet Explorer 8.0 (XP)
Windows Vista x64 Internet Explorer 9.0 (Vista)
Windows Vista Internet Explorer 9.0 (Vista x64)
Windows 7 x64 Internet Explorer 9.0 (7 x64)
Windows 7 Internet Explorer 9.0 (7)
However, contrary to that table, 5.01 is listed for Windows 3.1 as well.