I have recently volunteered to make a web map for a local non-profit. The map will be pretty basic. It needs to display Lane county, Oregon split into multiple districts, with a "central office" location for each district. I plan on building this in my spare time over the summer, and I want to be able to hand this off to them with very little risk of it needing any sort of future maintenance.
I have built a number of web maps using the ArcGIS Javascript API with ArcGIS Server, but I am planning on learning a different API since this organization doesn't have any ESRI software (or any GIS for that matter). I have been considering OpenLayers/OpenGeo. One thing to keep in mind is that this organization doesn't/won't have a server set up to host the layers of this map so I'm not sure how I would store and access the data. JSON maybe?
I'm currently unfamiliar with most non-ArcGIS solutions, so any advice would be appreciated.