The "correct" answer depends on what determines the time. Is it a fixed time that's always the same (or <= 3 different times)? And how long is it? Why do you want the user to know how long it will take? Is it enough time to grab a bite to eat? Or is it a short time the user will be waiting in front of the screen for?
Because if it's short, why show the user exact information? The equivalent of "one moment please" to keep them in front of the screen and make them aware that the game hasn't locked up in some weird way is enough. It would be different if it's a long time, because then the user may want to get up and start the coffee maker or whatever.
Also, if it is always the same delay, the user will likely get used to the delay, so the only one who really wants to know how long it takes in seconds is someone who dies for the first time. Later, people will know what to expect, so don't need that information displayed.
I personally find long artificial waits annoying, and rather enjoy how World of Warcraft handles it, where you immediately respawn as a ghost at a graveyard nearby and then have to walk back to your corpse to actually be reunited with your body. That way you have a penalty (you have to walk back to where you died), but you get a kind of gameplay and stay "inside the world" and do not really drop out of immersion. Of course, if you were in the middle of a mob when you died you may die again immediately, but hey, that can be solved by massaging the mob AI to avoid corpses, I guess.
I also like the approach Call of Duty has, where you simply respawn immediately in some random location and can immediately get back into the game. As you obviously died and didn't complete whatever objective you had, you've had a short delay already, and you might have to go back to your team, causing a second delay that encourages you not to die in the future.