[quote=@tobiax]
(The tabletop games you abbreviated)

Ah, don't know any of them, but okay.
[/quote]

DnD is short of the Dungeons and Dragons (basically the most common table top there is) and PF is for PathFinder (basically it was a revision of a previous DnD edition)

[quote=@tobiax]
We have three players and one DM, basically. But I'm not sure how many players we want/need.
[/quote]

I think that usually in most Table tops you want 3 to 5 players + DM. for a game. There is no rule for that though but I think its something that came from experience by others. by no means do I pretend there are no 1 on 1, 2 on 1 or 8 on 1 (or 2 if it actually becomes advanced enough, though that's probably just my opinion)

Also, for the DM, There is nothing wrong with railroading (even less if you just getting into it) but it might pay off to give the players an illusion of choise with going large scale rails. Don't sweat it too much though.