I like the Philips PET-range (7" to 10,2") but it seems like about 5 hours battery is what they offer, but the latest models has USB, SD-slot and a digital tuner and antenna. But all have a car plug, which some airlines offer (even in economy).
But if it’s just for the transatlantic flight, I’d suggest a carrier with decent inflight entertainment, which beats having a dvd-player on your lap for 9 hours.
Great features! The USB and SD card slot are enough to convince me except that I’ve inadvertently deselected the PET1030 by buying an Eee for a similar base cost.
Edit: Somewhat recently on a weekend trip to Portland, I learned that Hilton prevents customers from using their own media on the TV by crippling the TV inputs. I wonder if the only way to win that war might be small projectors. That or becoming a frequent/regular guest, I guess.
We bought this no-name player about a year ago, and it still works fine. Advantages: CHEAP, small, light, two headphone jacks, plays DVD+R/RW/mp3, comes with everything you need, including cables, remote, and car adapter, and can apparently be converted to region free, although I haven’t done it. Also, cheap. Did I mention cheap? Picture and sound quality are not bleeding edge, but they’re more than adequate. Cons: headphones are terrible (par for the course), and build quality is not topnotch, although we haven’t had any problems. I would estimate battery life to be about four or five hours, so if you’re going to Europe you’ll probably have to buy a spare (unless your plane has a power jack).