It sounds like you'd be better off with Manifold. The learning curve is very simple with tutorials and you could have an IMS site up and running in days. It is also very affordable at $245. Jumping into ESRI products for what you are looking to do will get very expensive very fast. Check out http://gis.gunnisoncounty.org/stable/mainpage.asp
as examples of high quality low cost IMS sites. Call the people who built them and see what they say about Manifold. or check out Manifold s website www.manifold.net.