Old-School/Planescape/Baldurs Gate...

Ok, I love these old-school D&D games... due to reasons of moving house I've lost the Baldurs gate 1, 2, 3 and Tales of the Sword Coast (bum) games and disc 3 of Planescape got broken...

I've tried to download Planescape as a 2-disc version and the first disc is good, but 2nd (which contains all the areas etc) won't work. I'm a total doofus with downloading and installing stuff, any help, advice would be much appreciated.

I wanna kill Gibberlings...