Windows 98 thru Vista compatibility

I need to convert and existing winhelp project into a format that will retain compatibility with windows 98, but will also be compatible with vista. I also need to be able to access captivate demos from within the help file. I used .exe's from winhelp, but I amt told that they wont launch from webhelp, and that I will need to create .swf files if I use htmlhelp or webhelp. I have used robohelp for years, was an original betatester, and I have not switched over to html or web help for a variety of reasons, so I really don't know how to choose what I should use. Please help me to understand what are the advantages and disadvantages of each. Thanks...