Reading the definition of Aura of Resolve, it is said the the paladin is immune to charm spells. Now, what does this mean? Is he immune only to the spells (mass)charm person/monster or generally to all mind-affecting spells?
Aura of Resolve (Su): At 8th level, a paladin is immune to charm spells and spell-like abilities. Each ally within 10 feet of her gains a +4 morale bonus on saving throws against charm effects.
As it says it works on spells and spell-like abilities with charm effect
Official description again
Charm: A charm spell changes how the subject views you, typically making it see you as a good friend.
So everything that you can push under this rule - is charm spell or spell-like ability. But not all mind-affecting spells. You can't control charmed creature, you can't force him to do something for you against his will. It's just affection changer.
To check particular spell you need to check spell school and subschool:
School enchantment (charm) [mind-affecting];
Spells that can force creature to do something against his will is Compulsion. Like Dominate Person and such.
Compulsion: A compulsion spell forces the subject to act in some manner or changes the way its mind works. Some compulsion spells determine the subject's actions or the effects on the subject, others allow you to determine the subject's actions when you cast the spell, and still others give you ongoing control over the subject.
Aura of Resolve gives immunity to any spell that says it is in the Enchantment (Charm) subschool, like charm person:
School Enchantment (Charm) [Mind-Affecting]; Level bard 1, sorerer/wizard 1, witch 1
See how it says “Enchantment (Charm)”? That’s a charm spell. Other enchantments, other [mind-affecting] spells, that don’t say Enchantment (Charm)? Those are not charm spells.
Aura of Resolve also makes you immune to any charm spell when it is cast as a spell-like ability, or any spell-like ability that explicitly states it is an Enchantment (Charm) or charm effect.
It would not make you immune to charm spells or effects used as a supernatural or extraordinary ability.
So Aura of Resolve is pretty good, but it is only a very specific and limited set of spells that it is providing immunity against.