Surprised a lot of users that Windows 7 and windows vista doesn’t support the view the images animation and this is true.
Windows Photo Viewer can view the gif images but without animated.
anyway You can open the gif image by Internet Explorer browser click right mouse button on any image and choose Open With from the menu,then choose the program selection, select Internet Explorer from Programs List and make sure you to select this option “always use the selected program to open this kind of file” then click ok button. see the picture ..
But if you want an easy solution you can download IrfanView this tiny program and free to view the animation ,many users use it.
you can download IrfanView from here.