Yes the picture is fine. And yes, it can always be used plugged in. The sound is a bit tinny, so I would not buy it mainly to listen to music. However, I've spent much good time with it watching DVD's.
I've been very happy with video quality (no pixelation, etc.). Cord is standard two-prong plug/charger. It's almost always plugged in during use, so haven't given battery life much 'real-life' testing (times I have used battery only, it went through at least 2 standard-length movies with no problem).
Hello, I have enjoyed my DVD player very much. I'm not a high tech person, but I do think the picture is pretty good. No complaints at all. It comes with an adapter to plug in for use or to charge the battery. I can watch 2 full movies and sometimes enough to start a 3rd when it is fully charged. The cord isn't very long... so if the outlet you plan on using is more then 3ft. you're going to need and extension cord. I did a lot of research before buying this DVD player and I'm happy with my decision to go with the Philips.