"Is there an efficient way to provide this information?"
Yes. Players should generally have an index card with monster defenses (at the very least) in their hands around turn 3. Enough attacks will have been made that the defenses will be obvious and it is an excellent way of speeding up combat. If you have a character who routinely makes monster knowledge checks, add sufficient detail to cover her worst possible check, then write additional information on the back. Inform your players when they are allowed to turn over the cards.
This way, there's no interruption of play as the players can read the cards outside their turns. You are not simply printing out the statblock for the players (though that's a quite viable option as well) and you are allowing players to use their knowledge skills to speed up combat.
The Rules Compendium (pg 130) suggests that a successful knowledge check reveals a creature's origin, type, typical temperment and keywords. If the hard DC is met or exceeded, the creature's resistances, vunerabilities and what it's powers do are also known.
I would be wary of adding further information to these checks, as there are items and powers specifically designed to provide some of these additional pieces of information.
As an example, a Foe Stone (level 12 Wondrous item) allows the following:
(Minor Action) Choose One creature you can see. You learn all the
target's vunerabilities, as well as which of it's defenses is lowest.
The Goggles of Aura Sight (Level 5 uncommon) are another example:
Power Encounter (Minor Action)Choose a target within 10 squares of
you. Learn the target's current and maximum hit point values, any
current disease or poison conditions on the target, and any disease or
poison effect the target can deal.
The Helm of Seven Deaths (Level 5 Rare) has a similar function as one of it's powers:
Utility Power At-Will (Minor Action)Effect: Choose one bloodied
creature you have hit with an attack during this turn. You learn that
creature’s current hit point total.
Several powers and abilities can only be used against bloodied etc. targets, so when a creature enters this state it should be mentioned. But as OrionDarkwood said, it is generally better to use vague terms such as 'it's looking very nearly dead' etc. rather than a specific hit-point value.
EDIT: As for Fortitude/ Reflex/ Will, a certain amount can be inferred from the type of creature - eg. big, hulking, things that like to bash stuff up close tend to be low on Will, but high on Fortitude, while weedy little spellcasters hiding at the back tend to be higher on Will, but low on Fortitude. Player's can pick this up fairly quickly as a general rule of thumb if they have several types of attack between them, as they'll take note of which attacks hit on lower rolls.
Best Answer
My current GM breaks this down into 10 (11 if you count meeting the DC) sections.
For achieving the DC, you get a name to call the creature and it's type(s). For every 5 beyond that you either select or roll for 1 of these 10 'blocks':
This has worked generally well for the group; having a decent Knowledge check is enough to ask for vital information but having a tremendous knowledge check nets you further rewards. This has the obvious drawback of some information being significantly more valuable (I'm looking at you Weaknesses and Immunities) or entirely useless (Weaknesses of something with only DR/- or no DR, vulnerability, or regeneration).
For this reason, we as a group decided to abide a social contract; we roll d10's (rerolling duplicates) and the GM's allows further rerolls of any that are not applicable to the creature. This balances the randomness of attaining knowledge on such a variety of creatures with the power of being able to ask specific things.
Alternately, at times, we have also established character norms; for instance, the Inquisitor would always ask the same questions, in the same order, regardless of if they had an answer or not. They "studied" targets in a manner that promoted knowledge of Weakness>Immunities>Special Attacks>Senses>Strong Attacks>etc. This worked fairly well for the short time that they survived, RIP Aleksandra. It negated randomly receiving bad information but balanced it by applying 'dead spots' where no information was gained.
One additional thing is we tend to ask for meta knowledge we already have first. Weaknesses is always the first thing we ask about trolls, to establish an in-character cannon of knowledge that you need to hit them with fire or acid.