Parasite Eve Q

Well I should be getting it in the mail in a couple week, so I’d best ask in advance.

When/where in the game is the disc change?

at the end of day 5, which is practically the end of the game.

How much is on disc 2?

1 or 2 dungeons, plus a series of final battles. You can leave the dungeons at any time until you complete the second dungeon (Museum). After that, you’re stuck.