The AC section looks pretty straightforward to me—you have two completely separate AC distribution panels (well, separate aside from a shared ground). This doesn't seem like the world's most convenient arrangement, but it's not hard to diagram out.
I would guess that the 30A breaker on the generator side fed a receptacle on the RV that the shore power cord was plugged into when used on the generator, and the 20A breaker there fed a roof air conditioner (as it seems to be labeled). The master breaker for the generator section presumably was mounted on the generator itself.
The shore power cord presumably connected to the 30A main breaker on the other (left) side, and the various branch circuits went off to their various locations. Note that this means one of the (apparent) two roof air conditioners could only be operated off of the generator, never from shore power.
The DC distribution may be split into two sections, one of which is "filtered" by the battery when the converter/charger is in use and the other of which gets "unfiltered" (noisy) output from the converter. When on battery power alone, of course, both sections would be connected to the battery. If this is the case, there are some switching relays in the converter/charger.
The charger/converter part is probably best used to hold open a door that would rather swing shut on its own. It could also serve to keep papers from blowing about in drafty areas. The AC and DC distribution panels would be functional and safe for that purpose still, but their arrangement is not very useful for more modern setups. Suitable glass fuses might be a bit harder to find than the now standard automotive blade type, though they are certainly still available without too much work.
You may be able to find the model number by tracking through the UL number (on a sticker in the AC compartment).
If you have some non-RV use in mind, you can use the components in any manner that makes sense and is safe. The "generator" section doesn't need to actually connect to a generator, for instance; it's just a breaker panel.
