[Arakon]

first of all, shoot your source of information, it sucks.

the origa is a 28 pin chip, long and thin.. so I'd say you got an origa.
the origa will not cause anything to overheat.
original PAL games will work fine, but keep in mind the ps2 will output a PAL signal then, which will be in b/w on a ntsc-only tv. if your tv supports PAL or has a RGB scart socket, they'll work without problems.
if not, you can look for pal/ntsc patches and patch a backup of the game to make it work.