Ooh boy, what reactions 
I still stand by my ruling: during the surprise round, orcs jump out (move action), then roll initiative. Characters are heroes, they react pretty fast in the face of danger, and have the opportunity to skewer the orcs with arrows or sword before the poor sods get a chance to know what happens…
Okay, that was the roleplaying part.
Now, down to the rules part:
So in the example, the two orcs made their Stealth checks against the passive Perception score of the characters. They get a surprise round.
Unless my english has become very bad (english is not my first language, by the way), the orcs only get ONE action, in this case a move.
If they're stupid enough to just jump out of the bushes without charging, or making a ranged attack, or any other ONE action that is effective against the adventurer's, then so be it. But they're orcs, they're not supposed to be very bright. And they're probably used to peasants running away screaming when they see them.
The problem is that if you don't play surprise this way, you have strikers and lurkers jumping out of the bushes, making a move AND an attack in the surprise round, dealing massive damage. It's unfair to the players (or to the creatures, if your players use the same rules). I don't like it. But YMMV

I still stand by my ruling: during the surprise round, orcs jump out (move action), then roll initiative. Characters are heroes, they react pretty fast in the face of danger, and have the opportunity to skewer the orcs with arrows or sword before the poor sods get a chance to know what happens…
Okay, that was the roleplaying part.
Now, down to the rules part:
A surprise round occurs if any combatants are unaware of enemy combatants’ presence or hostile intentions. For example, if you fail your Perception check to notice concealed enemies, you’re surprised. Or if supposed allies spring an attack and you failed your Insight check to notice the attackers’ traitorous intentions, you’re surprised. But if any of your allies made their Perception or Insight checks, they’re not surprised. PHB 267
So in the example, the two orcs made their Stealth checks against the passive Perception score of the characters. They get a surprise round.
THE SURPRISE ROUND
-Limited Action: If you get to act in the surprise round, you can take a standard action, a move action, or a minor action (see “Action Types”). You can also take free actions, but you can’t spend action points. After every nonsurprised combatant has acted, the surprise round ends, and you can act normally in subsequent rounds. PHB 267
Unless my english has become very bad (english is not my first language, by the way), the orcs only get ONE action, in this case a move.
If they're stupid enough to just jump out of the bushes without charging, or making a ranged attack, or any other ONE action that is effective against the adventurer's, then so be it. But they're orcs, they're not supposed to be very bright. And they're probably used to peasants running away screaming when they see them.
The problem is that if you don't play surprise this way, you have strikers and lurkers jumping out of the bushes, making a move AND an attack in the surprise round, dealing massive damage. It's unfair to the players (or to the creatures, if your players use the same rules). I don't like it. But YMMV
