Quote Originally Posted by ndsplayer19576 View Post
All I know about pbp's is that they are PSP executables, usually for things like firmware updates
True.

Quote Originally Posted by tyranim View Post
also, while im at it, i have this other one that came with all the disks included, but they're in .PBP files, so i have NO idea what to do with those
.PBP is also the format that psx games need to be in in order to play them on a PSP. If you really want to you can convert them back to ISOs using a program like "PSP ISO Compressor". I've never personally encountered the red line and circle thing before.