Looking at the size of the RDF files it's possible to fit the necessary files on to a single CD in a compressed non-browsable manner. If, however, you wanted to use it as a 'viewable source', you'll probably be looking around DVD storage quantities (the raw data alone takes up around 1.2Gb, so if you add the overhead for generated HTML files etc it'll more than double the size required).
I believe it is alright to burn the data to CD for usage in this manner as long as it complies with the ODP licence.
However, what benefit would this really have? A stand alone system would be similar to a library having a card-index and no books (as all the ODP is is just a great big electronic 'card-index' to the internet).