if all you want to do is simple stuff you can use any version of flash. It`s not until you get into doing stuff with action script (the codeing aspect of flash) that you have to really worry about versions etc. If i have flash player 9 installed and you use flash mx and build a swf for flash 6 then i can read it but someone with flah 5 will be promted to upgrade to the latest player.
As an alternative you can also check out Swish Zone
they have some lower priced stuff and editors which might suit your needs.