I believe .ico is the Windows icon file format, which, like the Mac equivalent of .icns, is a proprietary file format that only works on the OS it was made for. However, if there are png format versions you can use those just fine. Don't know what you mean by "How do I make these icon files behave!?" If you don't know how to use the png format, take a look at the instructions I wrote here:
http://www.pinkmutant.com/articles/Leopard/icons/icons.html
There's a link to even more detailed information, if you need it, on using png files in the instructions in the middle of the page.
Francine
Francine
Schwieder