If you have trouble downloading Reader after trying the steps in this TechNote, try downloading the Reader installer directly by clicking this link.
Look in your Applications folder for a folder called 'AppleScript'. Adobe flash player for mac os x 10.5.8 are verified to work properly and include all parts and accessories original or comparable substitutes.
If you can't watch this video because you do not have flash you can watch it a the link below.
Step by step instructions on how to Install Adobe Flash Player for Mac OS X.