Exploiting the PS2; can it be bad?

I'm new to the exploiting game so I was wondering could it do damage to the PS2? And if you do change some settings, can they be changed back to default?

OK I just did some more reading and I'm wondering if I try to play my PS1 game, will it run KeyLauncher ever time? Is there a way around this like not using TITLE.DB if you have Swap Magic?

to play your PS1 game just boot without the memory card in.

the exploit sits on the memory card. take out the memory card, or delete the "Your system configuration" file that's on it, and it'll be as if you never had an exploit.

use launchelf instead of keylauncher