We're not quite at that stage of getting a DVD player. Have two kids, one is about to turn 6 and the other is going on to 8. But I sure am looking forward to when they buy a DSi or DS Lite or whatever each! They have enogh saved up so just waiting to see if there are going to be any good deals around Xmas!
It's not like the good old days where they would eat, sleep, look out the window then eat some more and sleep again! Silence when it rarely happens is bliss and if it goes on for longer than 5 minutes it certainly reminds me of the early days (no kids).
I'm hoping the DSes will be ample for those times when everyone needs a bit of peace and quiet because the kids certainly don't know the meaning of those words lol. Certainly nothing more distracting than bickering kids in the back too.
Sure they should just look out the window just like they should just play outside at home, but it's not always practical.
I did consider the PSP because it's more versatile but I think it's geared towards older kids and not as many games. Could be a consideration for some of you with the older kids though because they can play movies etc and the screen seems to be good quality and graphics.
I've watched some home made vids on my little 8gig ipod and I'm quite impressed with the video quality even though the screen is rather small, so I wouldn't rule out an iPod touch or iPhone etc providing there wasn't going to be a big associated cost (internet / phone or whatever).