Different strokes for different folks.

I would say that from a pure accuracy standpoint the handheld will be the most accurate, when it is shot properly at it allows the release to happen through back tension as opposed to just mashing the trigger.
The flip side is that it takes some time to learn just how to shoot it properly. Anybody can get the release to go off, however getting it to go off with a total surprise and good shot execution in a hunting situation tends to be more difficult.

The easiest type to get used to is by far the wrist strap type. This is especially true for beginning archers. It sucks big time to accidentally drop your release out of the stand when going for your bow.
If you do go with a wrist strap type, I would recomend getting one with a good, crisp trigger. Something like the TruBall Short-N-Sweet or any of the Carter releases.

IMHO the TruFire Hurricane and similar releases with long trigger pulls to get the release to fire are one of the #1 causes of target panic and punching the trigger in new archers.

Get a good release from the start and avoid building bad habits.