First off, hold off on getting things until someone with a higher post count or a moderator
stops by. I originally tried going to the SCP site and getting all the files, but some of it
was out of date compared to files here floating around the forum. I could point you
to some files, but even that information is likely out of date already. So it is best to wait.
Some basics you will need...
The Freespace SCP main files
Updated Media VP's
New multiplayer pxo file
You might mention if you are on broadband or dialup, because that will dictate
what you will want to get in the way of files. Some are very large in size, and thus you
would not want to try to slowly download them over dialup. Although this can be overcome
if you live near a restaurant with WiFi or another hotspot.
Mods or Total Conversions are a different story, and will need additional files to those above
in order to change the gameplay, add ships, etc.