Combine PDFs and animation sounds easy, but it is often harder than it needs to be. Here is another trick that might make it easier.
InDesign CS5 has more interactive features that ever, but you should be careful with the media that you use.
Animation is really fun with CS5, but if you try to directly export your InDesign layout to PDF you will not like the results unless you know about this workaround.
Read about all of the geeky detailed inner workings that happen when you export your InDesign CS4 layout to Flash.