You have to first uninstall windows live essentials 2011 with the instructions here, How to uninstall Windows Live Essentials
Then you have change the way you receive windows updates otherwise the program will reload,
Go windows updates, click on the change settings link on the top left,
Uncheck give me recommended updates the same as important updates,
Above that section change it to, ask me before downloading and installing windows updates, and save.
Review updates in the future.
Now you can download the original vista photo gallery, they renamed it live photo gallery but it still has the simplistic user interface, Download Details - Microsoft Download Center - Windows Live Photo Gallery
There is an x-p version of windows live essentials that also has the same simplistic interface that works very well with windows 7, Windows Live Essentials for Windows XP