Tip - HELP!! I can't watch dvds on my laptop anymore??

I always was able to insert a dvd and it would automatically pop up to play. Now for some reason...it doesn't do that. And when I try to pick a media source to play it..it says no disk found even though one is in there.  Please help....this is wonderful for my toddler to view movies on since we don'...
Tags: operating system, software