As far as I know, the second player floats back onto the screen in a barrel as soon as they die, and it's up to the remaining player to jump towards the barrel to free them and bring them back into play.
They can leave them floating in the barrel - "time out", as the product description puts it - whilst the other player passes a difficult section of the level.
It's worth reading a couple of reviews on the co-op though to see if it'll be suited, though. This is alledgedly a difficult game. On top of that, I don't think the characters are evenly matched - one has more power than the other. From the Eurogamer.net review:
"Unfortunately, the similarities between DKC Returns and the original games also extend to the multiplayer mode. Just as it was in those games, it's a bit rubbish. One player controls Donkey while the other is in charge of Diddy, and you're always on-screen at the same time. Or at least that's the plan - in reality, with so much happening on-screen, such large character sprites and that close-up camera, you spend a lot of time waiting for each other to catch up.
When it comes to the on-rails levels the two-player mode is seriously flawed. You're both in the same boat, or rather mine cart, so you can't tell who messed up that jump or who was responsible for that leap to victory. Plus, if one player makes a mistake you'll each lose a life. This makes it easy to burn through those red balloons, and impossible to complete the trickier levels if you're playing alongside an idiot.
So forget the formal multiplayer mode. You're better off sticking with the tried and trusted formula my brother and I patented in 1994, where you swap the controller every time someone dies or finishes a level. We call this mechanism, brilliantly, lifeforalifelevelforalevel. We employed it when playing DKC Returns the other day and it was great fun, even though we now have a combined age of 60."
So if you're buying for the multiplayer only, it might be worth reconsidering. I don't know myself, as the game isn't available here in the UK as yet.
no the game is full co-op its just when ever a player dies, you got to beak em out of a barrel(just like the original) and you should check out kirby's epic yarns its also full co-op(great game by the wayKirby's Epic Yarn (Wii))
Arway - the reportedly unforgiving nature of the gameplay has indeed also given pause for thought (though there is a NSMB cop-out option I believe if a level proves impassable). I'd add that you and your brother were clearly a far more civil pair than my two, at least when they get in front of the Wii (angels otherwise, of course)!
Mr Ibrahim - without a doubt, I'd purchase 'Kirby' over this but unfortunately it seems to have been pushed to 2011 here in the UK. Big mistake by Nintendo, as it looks the perfect Xmas family game. Should have delayed 'Epic Mickey' instead, by the sounds of it...sad to say.
No probs! You're right, there is a Super Guide feature where the computer will take control of Donkey Kong should the level be too difficult. The player can retake control whenever they wish to, or leave it to finish the level for them, in a similar fashion to New Super Mario Bros. Wii.
"I'd add that you and your brother were clearly a far more civil pair than my two, at least when they get in front of the Wii (angels otherwise, of course)!"
Ha ha ha! Although that wasn't me, it was the reviewer I'd quoted from the Eurogamer website!