To start, you will need to use the development version of GDAL. It can be downloaded here:

http://www.gisinternals.com/sdk/

In my case, I used:

http://www.gisinternals.com/sdk/...

The specific file I downloaded was:

release-1600-x64-gdal-1-8-mapserver-6-0.zip

Unzip this file into a folder on your computer. In my case I didn't want to install the software but I wanted to run it from a local folder. I already have the non-development version of GDAL installed under OSGeo4w and I didn't want to interfere with that. Once the file in unzipped you will need to start the DOS command line. This can be done by running the CMD.exe program on all windows computers. Use the DOS command CD to change the directory to the folder gdal_dev\bin\. Use the DOS "path" command to temporarily change the system path to this folder.

For example: Path e:\gdal_dev\bin\

Once the path is set to the .dll files, you can now change the directory to where the app files are. For simplicity, I copied my PDF file to this apps folder as well.

CD E:\gdal_dev\bin\gdal\apps>

I used the gdalwarp command to resample the PDF file to a ground resolution of 2 meters. I used the lanczos resampling method. I quickly experimented with the various resampling methods and I found this one to have the best looking output. The ouput .img file can now be opened in ArcMap.

gdalwarp -r lanczos -tr 2 2 -of HFA NJ_Morristown_20110412_TM_geo.pdf NJ_Morristown_20110412_TM_geo_2m_lanc.img

Note that USGS has Historic GeoPDF files here: http://nationalmap.gov/historical/
USGS has current topographic maps here: http://store.usgs.gov/

Please let me know if you have additional ideas.