Hi John,
Adobe Flash player is needed for you to watch such things as reports on, say, BBC News website, but it is also the driver for many adverts with moving images on commercial sites.
If you do not have it (Shockwave Flash plugin) the site will usually tell you that the report/ad will not play and you will need to get Adobe Flash Player or the latest upgrade.
Providing you are directed to the Adobe website for the player/upgrade everything should be OK, but a word of warning! As with many downloads you can also get other "stuff". Depending on the product, Adobe could offer to install for you some junk from McAfee, Google Chrome Browser and Google Toolbar, be sure to untick the boxes if you do not want these things.
But try this first:
http://get.adobe.com/flashplayer/otherversions/ and make sure to untick McAfee. Simply run the installer from the site.