Two easy and rapid questions.

[Alex_UNLIMITED]

1) Can my large eidolon with reach attack a creature even if the creature is charged in my direction and I am in my eidolon's reach?
2) Smite evil/good/law/chaos of summoned creatures bypass the DR?

[Weables]

1. Please rephrase your question in a way that makes my brain hurt less. 'I am in my eidolon's reach' makes little to no sense.

2. No idea. I don't think so, as bypassing DR is a paladin specific ability. Just because it has the same name, doesn't make it the same ability.

[concerro]

1.This question needs to be rewritten.
2. No. The summoned monster smite is not the exact same as the paladin smite.

[Alex_UNLIMITED]

1) I'm charged by a creature. I'm adjacent to my eidolon. The creature is charging in the line where I am.
Can my large eidolon with reach makes attack even if i'm there in the line of the attack?

[concerro]

I understand now. Yes the eidolon still gets the attack of opportunity.

[SlimGauge]

Does cover negate AoO's ?
Because if I'm understanding the OP's question correctly, his summoner is between the eidolon and the charging target.

WARNING, BAD ASCII ART FOLLOWS

0.0.0.0.0
E.S.3.2.1
0.0.0.0.0

E = Eidolon
S = Summoner
0 = unoccupied
1 = first square entered by charger
2 = second square entered by charger
3 = third square entered by charger

In this case, the eidolon can reach into 3, but anyone in 3 will have cover because of summoner in S. If someone charged through 1,2,3 they would NOT provoke from the Eidolon, because it is the act of LEAVING (not entering) a threatened square that provokes.

Now if the situation where this

0.0.0.0.0
E.0.0.0.0
S.4.3.2.1

Eidolon can reach 3 and 4. Eidolon gets an AoO on charger when the charger attempts to leave 3.

[concerro]

For some reason I was imagining that 10 foot reach as 15 reach.
If SlimGauge's picture is correctly depicting the OP's idea then the attacker is safe.