Door Stuck On Opening

It may be that the latch isn't releasing all the way. Does the door hang up the same with both the inside release and outside handle? I can't remember if your year has it, but, some later cars have an adjustable link to the latch release. It could be that some of the linkage inside the door is worn/bent or the latch is. You said you installed another washer under the striker and it didn't help? Try adding 2-3 washers and try again. The head on the striker can hang up in the latch if it doesn't hit in the right spot. By holding the button in while closing the door, it should close and open without hanging up on anything.