Oh sweetheart! Of course the surgeon will also check your cruciates. He will check every bit of the joint and spend a while doing it as well! Knee surgeons have a check list of things they look at when they scope a knee and look in every nook and cranny.
But yes, believe me, that much pain can come from just a meniscus. Just been down that road myself! And the pain seems to permeate every other part of your leg as well. Are you taking pain killers on a regular basis? If not, you need to. It will help you be more mobile and keep your muscles in good condition for after the op.
However, I have to mention - from what you have described here, a 'degenerating meniscus and ACL' can sometimes be an indication of early arthritis. The picture of pain and disability you have is indicative as well so don't be too surprised if the surgeon mentions this after the scope.
However, don't despair - an arthroscopic tidy-up and wash-out could settle things for a good while. Good luck - and get those pain killers!