What are the stats like Strength, Dexterity, Intelligence and so on? Will a particular weapon or armour need to have a high or low Strength or Intelligence?

I'm pretty sure I saw that there's a stat called "Power" that judges how much damage you do so you won't need to worry about balancing Intellect and Strength if you play something like a melee mage. I can imagine the rest is all your regular elder scrolls fare like stamina and health.

There aren't any. When you level up, you chose health, stamina, or magicka.

he means on gear.

The Elder Scrolls has moved away from that system for good with Skyrim I think, you will definitely see things like Health, Stamina and Magicka as primary stats from now on. And things like Crit rate/damage, armor rating and resistance, among other things, for ESO.