How flash loads on different systems?

I’m currently working on a MAC, and I just finished my online design portfolio website. I was working in flash and everything seems to be working correctly on my side. I’ve tested it on a few computers, but something odd keeps happening when I load it up on PC systems.

For some reason when the site loads, you have to click the loaded flash section before you can start using it. So basically it’s only a static picture until the user clicks on it. I was wondering why this is happening, and how I can fix it… because I checked and no other flash things do that.

Thanks in advance.