The .art extension was used by several art programs and also by AOL
for images. It can be tricky to open these days. Probably the quickest
thing to try is downloading AOL’s desktop software. It’s free at this
link: http://discover.aol.com/products-and-services/aol-desktop-for-windows
From what I can tell, it will still open .art files. I can’t test
it out myself, since I don’t have any .art files. Once AOL Desktop has
installed, click “File” in the upper right corner and choose “Open” from
the drop-down menu.
You should be able to select your files to open.
You can then view the image in a photo viewer.
You may be able to click “Save” and save it as the more popular .jpeg file extension.
I hope this works for you!