Dear Sean,
For the purpose of your project I would recommend to use QGIS for creation of layers (shape file and rasters). QGIS can use a lot of the mentioned functionalities of GRASS as it has a GRASS-plugin.
For serving the shapes and rasters online in a webmap I would use geoserver to serve them as a wms (web mapping service) and consume it on the same machine with openlayers.
we have a lot of content regarding this:
http://www.digital-geography.com/tag/openlayers/
http://www.digital-geography.com/tag/qgis/
you may find a good overlook here: http://www.digital-geography.com/types-of-web-maps-concepts-and-possibilities/
best wishes, riccardo
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Re: Open Source GIS? Recommendations
[re: sean2me]
