I'm ending this Natsu vs Gildarts, let me show you while Gildarts would blitz-stomp Natsu. (IDK to use spoiler tags)
Gildarts cracks an entire town by tripping.
http://ru.fairytail.wikia.com/wiki/Файл:Gildarts'_Crash_Magic.png
'poof' speed AKA speed feat
http://www.mangapanda.com/tale-of-fairy-ice-trail-koori-no-kiseki/4/14
Instantaneously punches 13 dudes with one arm
http://www.mangapanda.com/tale-of-fairy-ice-trail-koori-no-kiseki/4/18
Punches someone thru an impregnable prison larger than a mountain leaving a creator around his body. Didnt mean to hit him that hard.
http://www.mangapanda.com/tale-of-fairy-ice-trail-koori-no-kiseki/4/25
Gildarts moving several feet and attacking before Natsu reacted
http://vignette2.wikia.nocookie.net/fairytail/images/d/d9/Lapointe_is_hit_by_Gildarts'_attack.gif/revision/latest?
cb=20140615221949
"Natsu nearly burnt down the GMG with one fire attack"
Gildarts wasn't attempting to do anything, he tripped and cracked a town which is more impressive than Natsu trying to set ablaze the GMG.
"Natsu ran through hundreds of monsters which is more impressive than Gildarts punching 13 fodder"
If you think Gildarts is incapable of replicating that feat, you are wrong. They may have been fodder, but it showcased his speed. Gildarts has casual mountain busting punches. If you combine those two, it means that Gildarts can throw out several mountain busting punches instantaneously. I'm also going to throw out the fact that even if Natsu is fast(people keep saying this, but I don't recall anything feats that showcase exceptional speed), Gildarts is way faster. The KotSH feat should tell you that.
"Natsu destroyed the TOH"
Gildarts destroyed a mountain with a casual punch
"Natsu durability is too high to get stomped by Gildarts"
His durability may be high, but I do not think that it has improved all too much during the time skip. We haven't seen anything showcasing an increase in durability, only strength. Natsu was beaten very badly in a fight against Gildarts where he wasn't even moving. Natsu isn't capable of reacting to "Poof!" speed. KotSH feat showcases that Natsu is in fact, slower than Gildarts. He didn't even move before Gildarts was already several feet away and attacking.
Gildarts is far too fast for Natsu. His punches are simply too powerful and he can throw them out very quickly. Natsu's magic can't touch Gildarts because he would destroy it. Natsu could only hope for a draw in a fight with Gildrarts. In the end, we have still never seen Gildarts go all out. That is not the case with Natsu.
Gildarts casual punch levels the landscape
http://www.mangapanda.com/fairy-tail/497/13