Sounds like the DVD lazer may have either become dirty or faulty and only works intermittently,if it plays cd's ok then it may just be dirty but as you say it wont play films either it sounds like the Lazer has failed.
Galaxy Note 8 vs iPhone X
Graphic tees: 14 best websites to find your next T-shirt
How to update iOS on iPhone or iPad
Les meilleures applications pour enfants 2017