What is the strongest armor in elder scrolls 4 oblivion

Aside from Daedric armor Glass is the next best thing. The Imperial Dragon Armor sucks, the enchantment is terrible.

If you have the expansion you can also craft Madness Ore Armor and Amber Armor which is just a one step upgrade of Daedric and Glass.

Either way you'll want armor you enchant, it's better than anything you find. 100% Chameleon is probably the 'best' enchantment since it makes you effectively invincible but it also ruins the game by removing any challenge. I prefer damage reflect, spell reflect, spell absorbtion, damage absorbtion, fortify strength (boosts maximum carrying weight the most, better than feather), and fortify intelligence (more magicka = better spells).

You could also just enchant a set of clothes with nothing but "Shield" which ultimately yields about as much armor as a full set of glass or deadric but you don't have the bonus of having useful enchantments.Happy Questing!