Like many used gamers, I have a huge stack of scratched now worthless PS titles that i have been trying to get back. I want to know can I play them on my PS or do i need to get a chip like the PS2?

Not necessarily, unless you want a foolproof method that works 100% of the time.

The chipless method includes...the disk-swapping trick and PSX emulation.

ps-xchange 2

is guaranteed to work for old psx and ps1. if it don't work, blame it on your burning method. or a crap iso. who knows. one or other especially if your trying to make the iso's yourself. that's even harder to do. O-o i always get something wrong.