I was just wanting to know, ive played and betten dishonored by being a non-lethal assassin. I've heard that the way you play effects the end. Is that true? If so what one has the best ending and the most fun. For each play style is there certain Upgrades/Powers i should use that will help me get threw the game faster/more effectively?

It is true that chaos effects the ending, yes.

Hmm...if I was playing entirely non-lethal, the powers I would get are...

Blink 2
Darkvision 1
Bend time 2
Possession 2 and
Agility 2

I finished with clean hands on very hard. By the end, what I had maxxed out (if you're OK with Merchant of Disorder instead of Mostly Flesh and Steel achievement)

Blink 2
Agility 2
Dark Vision 2
Possession 2
Bend Time 2

I threw the rest into Vitality, but that's just for craps and giggles.... don't need anything else for non-lethal, imho.

Invest in getting Boot Stealth 1 and 2 as soon as you find the schematics. Also Mask Optics for more precise shots, Crossbow Range and MOST IMPORTANTLY,
(as in, get as soon as you can) Combat Sleeping Darts.

If you get lucky and get the Strong Arms bone charm... hug it, equip it right away, love it forever and ever. Best charm in the game for ANY playthrough.... but especially
non-lethal. And there's another one, Fleet Fighter, that lets you move at full speed with weapons drawn... which is also very handy.

And yes,

Wind Blast 1 might be an alternative for non-lethal. Destroys wooden boards and gets rid of fires. I can think of two spots I would have used it. It's not powerful enough to be lethal either. The second upgrade has enough force to kill if there's a solid substance (wall) to knock people against. That would go last though since your main MO will probably be don't be seen, don't get caught.