Jiraiya should be easily able to capture Zabuza and Haku, which i will now demonstrate by countering all of your techniques.
Countering Silent Killing and Hidden Mist
Jiraiya is very proficient with barrier based techniques, so the Hidden Mist Jutsu will not be of much use or effect against him. Jiraiya would be able to use the Barrier: Canopy Method Formation, which allows him to detect all movements within a wide radius and block attacks from the enemy. With this, Jiraiya would be able to detect Zabuza and Haku if they do try to attack him in the mist, thus proving it useless.
Countering Kenjutsu
Jiraiya would be able to counter Kenjutsu through the fact that Jiraiya is more faster than Zabuza. Jiraiya boasting a speed of 4.5 in the databooks while Zabuza has a speed of 4 does show that Jiraiya should be able to dodge any sword slashes that come his way, and is also reinforced if Jiraiya has Barrier Canopy in effect. Also, Zabuza's blade has not shown any strength feats as Kakashi's kunai was enough to block it so again Jiraiya should have no trouble with that.
Countering Demonic Ice Mirrors
Jiraiya could simply use Needle Jizo to block Haku's senbon which would be more than effective in terms of defence due to the rigid nature that his hair takes upon effect of this jutsu. Again Barrier Canopy jutsu eliminates the risk of a surprise attack.
Offensive Moves
Jiraiya has a number of offensive moves with which he could potentially win the battle with. Firstly, Jiraiya could use he Toad Bind technique to trap one or both enemies in the oesophegus of a toad, which would also restrict movement of the enemy. With this in effect he could potentially finish one enemy and then resume battling the other, where it qould be a simple one on one. Or it could be used on both enemies at the same time.
Jiraiya also has the powerful sage mode, in which if he achieves in the battle, he will most definitely win. One way to acquire the sage mode in the middle of a battle would be to to use the means of infiltration to assist him in this process. Jiraiya could potentially summon a toad that he can hide in, acquire sage mode and then return to the opponents, and then finish them off with Frog Song or countless other jutsu. However, Jiraiya was shown able to fend off Animal Pain and still achieve Sage Mode, so fighting against Zabuza and Haku would not be too much of a stretch to do the same thing if not easier.
There are countless other jutsu that Jiraiya could do to win, but i will now hand it back over to you. (I have to go now, so will reply tomorrow.)