Some of these guys can be a pain in the ass if u dont know what your doing. I think these are the easiest ones to defeat w/a few tips for combat.
-Mix up a few Pain Killers in the blender ( Vodka + Vodka)
-Try to have a powerfull mellee weapon like the Sword located on the walls of Americana Casino or the Large Wrench.
-You can actually leave the scene of the fight to heal up.
-The higher the level u are, the better.
--------Antoine: tastes like chicken side mission-----
(If u dont care about survivor health, grab the 3 from rock heros side mission & arm the 2 guys w/guns. They will help shoot & distract Antoine while u slaughter him w/a melee weapon. The rock chick might get stupid and try to shuve him & get killed in the process. Either way shes helpfull)
-------- Bibi : One hit wonder side mission---------------
(Talk to her, do what she asks & play the mini game. Make sure u get a tux & shoes from modern buisness man)
--------Randy: Here comes the groom side mission-----------
(Good to have a shotgun or 2. Just keep the pewe wall between u and him & he will never touch u. Everytime he comes around to u, jump from one side to the other. Shoot him a few times & u can melee him thru this wall as well.)
-----------Carl: Mail order zombrex side mission-----------
(Bring Dani the bride u rescued from Randy & Arm her with a machine gun LMG. Order her to stand inside the little newstand right next to the broken mailcart. Block off the entrance w/one of the green newsboxes. Then examine the cart, thus starting the boss fight. Dani will start shooting him & he wont be able to get to her. He will be distracted, enabling you to easily kill him.
-----------Seymor: WWJWD? Side mission-------------
( Like always, prepare w/some pain killers. Now just whack away at this guy w/your sword. He isnt that hard)