FF4 on psn is not a version of the ds game. It is a 2d remake and is pretty good. Everything else is about right, but I'd be careful about FF5 because the PS1 version of the game never worked on a PS2 or PS3 (I haven't tested the psn version myself).
wok's forum posts
-For example, you don't necessarily pick up a quest to do the following, but if you kill all the necromancers in an undead barrow, a shade you free at the end will reward you.
-However, to help you find these events, various NPCs you talk to will tell you where they are happening and put a marker pointing them on your map, which is obviously totally different than receiving a quest.
You can use a homeward bone to warp out of boss areas. Try to run in there, grab your souls, and warp out. Also, don't worry too much about losing souls. It happens.