There should only be 1 disk needed to play a game on PlayStation 1's, PlayStation 2's, PlayStation 3's, and portables versions. Just insert the main gaming disc if there are 2 of them (for some odd reason).
No. Because The Playstation 1 Is Too Old.
yes
No.
most of them can be played on a playstation 2
Yes it can be played.
no
No. You can play Legitimate PS1 games on a chipped PS2, but you cannot play PlayStation 2 Games on a PlayStation 1.
nope.
No, it can not.
Yes, the PlayStation and PlayStation 1 are the same thing, PlayStation 1 being a retroactive moniker for the original PlayStation. As such, both use the same medium for games, a black CD-ROM.
Actually, all you have to do is stick the game in the PS2, even if it's a PS1 game.
no you can not play a PS2 game in a PS1 console