My primary concern stems from when you said you got an error "Too many programs open." In my personal experience, this can occur when you simultaneously attempt to install the same applications (accidentally). Make sure to check your Task Manager and, if (when) you attempt to reinstall, before opening the disk installer, ensure that NO other X-Plane 10 applications are running (select "Show processes for all users"). This will ensure that no X-Plane applications (installers) are running simultaneously (if possible). Once installing, please be patient. Some files can take time to install. Even when it seems to pause, let it run without interruption. Do this for the following 7 discs.
If this does not solve your problem, there can potentially be an error with the DVD (thus requiring a new copy), in which case you can contact Laminar Research directly at http://www.x-plane.com/support/.