Wrong icon showing for program type

This is a minor irritation, but I get bugged by these little issues

I had Firefox set as default browser and working as such, but the icon
showing was Opera. If If I right-clicked on the icon and then Open With
and Choose the Default Program (wording may differ--my setup is in
French)Opera was selected. If I selected either IE or Firefox that
program would become the default, but the icon was unchanged. If I went
back into Choose Default Program I'd find, once again that Opera was
selected.

As I don't use Opera I uninstalled it. Now it's the MS Word icon that
shows and won't go away! In Choose Default Program it's Microsoft Office
2003 component which is selected.

Curiously, though I can't get the Firefox or IE icons, if I select
SeaMonkey I get the right icon, though when I go back into Choose the
Default Program it's still Microsoft Office 2003 component that is selected!

I tried running the icon fix in TuneUp Utilities but it didn't fix it.