On the whole laser rot is invisible when you're looking at the actual disc, but it can in some cases be seen. Does the disc play at all? I've never seen marks like that on a LD but I used to have a really old CD-R back from the days when they suffered really badly from laser rot and it looked just like that.

I'm not sure. I have the same thing on my Barbarians Laserdisc, but it plays just fine.

i think to answer your question though, 'laser rot' is generally something that you can't actually see on the disc, but it causes playback problems. mostly artifacts and 'snow' in the picture, and it causes audio playback problems as well. my copy of The Cable Guy is almost unwatchable at the beginning of the second side, as the audio is really garbled and the video is very bad during the same part too. however, the disc itself looks fine. your disc almost looks more like its gotten water damage somewhere. i've never seen that before either.

Ok. Thanks. I think I have a few disks like that. (Scanners is coming to mind. Robocop skips after 20 mins on side 1 and can't play side 2 at al cause it just skips right thru it. Might not be laserot but is a problem) I'm getting ready to watch my entire collection. (Theres atleast 30 films I've have never seen before) and see if theres any problems with them. It's odd that water damage will look like that but, even though I've been collecting since '98, I'm still new to the scene.