Q: Converting AppleWorks files for the future

I have an old eMac that can still open older files. I have a few CDs of various files I have saved over the years that I am trying to convert to formats that will be readable in the future...IE archives, Compact Pro archives, and of course AppleWorks files.

My question is if there is any format that will preserve formatting (boldface, type sizes, etc.) that is likely to be readable in the future? I'm ooking for something editable and more lightweight than PDF.

I thought RTF would be a good choice, but it seems that every app has its own interpretation of RTF. For example, formatted AppleWorks files converted to RTF do NOT preserve formatting when opened in Apple's Preview.