For viewing exif data on the web, I like Firefox and Fxif (though there are other plug-ins that do similar stuff.) Offline, I like Irfanview - make sure to download the Plugins/Addons to get exif functionality. All of the above is free and there are no ads, spyware, etc.
There are a ton of other programs, too. If you want to literally extract the data, you might want something like Exiftool, which can do just about anything but is a command-line tool, so it's not very friendly.