Alrighty-- you have quite a lot of questions there and some of them are a little tricky, but I'll try to answer them all. I think the main question is, and correct me if I'm wrong, but I think it is: If I've got an old Navnet VX2 I bought used what do I need for GPS and fishfinding?
The components you list are pretty much everything you need, but there are some modifications that sometimes need to be done, or a cable that needs to be added. Some DFF1's have jumper settings that are set up for the NavNet 3D so you need to be careful about that-- talk to a Furuno Tech or check out the installation guide to see what you are working with.
Also you state that you have an "Airmar" transducer-- this is just not enough information for me to conclude if your current transducer will work-- what unit was that transducer hooked up to before? Also Airmar can determine which transducer you have if you get the information off the tag near the actual transducer. Some transducers can be pinned out so you can use your existing transducer on other systems, but not all of them, so it is important you get that information first.
Now as for the Radar capabilities-- if you are not using Radar then simply do not hook up the Radar antenna! The unit still functions as a chartplotter/fishfinder without a Radar. The GPS and Fishfinder capabilities are mutually exclusive to the Radar, meaning they function independently, so having the Radar missing will not effect the other functions.
NavNets all have the capability of being WAAS-- it just depends on what antenna you hook into it. The BBWGPS for instance is a WAAS antenna and so that would work fine. If you have an older antenna from a NavNet version one then you might not be getting WAAS-- it just depends on what exact antenna you have. Also-- if it is not a Furuno antenna, but is a NMEA outputting antenna then in most cases you can hook that up through the NMEA interface (you will likely need the NMEA interface cable).
The chart may work, but you need to be sure that is the SD card version. And of course you cannot switch a unit to C-map or Navionics: once you have the machine in a certain cartography it is like that for good.
Keep in mind, too, that you only have network port, so if you are just hooking up the fish-finder then you are fine, but if you are adding another station or weather then you will need to incorporate a network switch. This may not even apply to you, but I figured it was worth mentioning.
So to answer your question: yes and no. It just depends on the details. Please let me know if you have any questions. And remember that these components can all still be ordered through us if you need them (like the NMEA cable: part number 990213, the WAAS antenna: 130001, the transducer: depends on what your deadrise is, ect...). Thanks,
Bobby
NavNet2 ?'s 
