How big is R on CRAN #rstats by Ajay Ohri.
3.87 GB and 3786 packages. Thats what you need to install the whole of R as on CRAN
Just in case you are looking for a data set to map to a graph. Such as packages that call other packages, etc.
Think of the resulting graph as being a lens for viewing R literature on the Web.
(Curious what sort of download time you get?)