You don't say if these are all the same model of DVD? Not impossible to get a bad run of DVDs, especially refurbs or low prices units.
The first problem has to be in the DVD players themselves.
The second problem is probably the DVD player. If it does the same thing on different movies then for sure.
The last problem could be a bad input on the TV, bad cable or the DVD player. Try a different cable and another input on the TV.
Make sure that the input on the TV is working by connecting something else to it (cable box, etc).