For using a map on your website, the best option is probably OpenLayers. http://wiki.openstreetmap.org/wiki/OpenLayers
It will give you a slippy map, and you can add overlays on top of it. So you can add a layer with icons to click, which will show information/photo. You can start with this example here: http://wiki.openstreetmap.org/wiki/Openlayers_POI_layer_example