First off, here is my old answer,
Needs some help,
Emboar doesn't need flamethrower, just go ahead and give him head smash.
With golurk don't use shadow ball use shadow punch ( Golurk has a higher atk stat than sp atk. )
and use Hammer Arm, ( for coverage agaisn't dark types )
No solarbeam on virizion, I would use leaf blade, then have swords dance instead of giga drain.
Volcarona would do better with flamethrower than heat wave.
Psychic would be pretty good on him, or you could use HP electric or water.
thats what I have to say about the team, it was pretty decent though, and please post natures and items, next time.
Now for the things you asked in this one.
- I think You should go with earthquake since you already have dragon claw.
** Iron defense makes it more of a wall, while magnet rise just makes it have on less weakness, its really your choice they are both fine.
*** I personally preffer sawsbuck
I would try a set like this,
Horn Leech( or is it wood horn? )
Double Edge ( Wicked stab and you can heal the recoil with horn leech )
Wild Charge ( Same circumstances minus stab )
Jump Kick ( I think you get the point )
**** I guess it works
***** I personally don't think solarbeam is very good without sunny day, so it doesn't do great for water types, because they would hit you when you charge. An HP grass or Electric could fix this.
Hope this helped alot. :D