How to best render in v ray?

EXTERIOR LIGHT:IRADIANCE MAP+BRUTE FORCE

INTERIOR LIGHT: RADIANCE MAP+ LIGHT CATCHE

There is no simple answer to this question. Which sparrow is better in the flock? But you can do is following. If you want to render exterior scene, google Exterior Scene rendering in Vray and you will get good tutorials. Same is the case with Interior renders.

You can also check http://viscorbel.com/shop/vray-interior-lighting/

I didn't like this guy’s rendering setting and I feel like these are very high and some settings he misinterpreted. 

But all in all its good tutorial.

Quick settings are in Color roll out. Set the Gamma to2.2 and check "don’t' effect colors"

Set the GI On and set the primary bounce to Irradiance map and secondary bounce to Light Cache.

Set the irradiance map preset to Low and Light cache setting to500 rays. That’s about it. If you feel that edges are being blurred you can turn on Enhance details in Irradiance Map and turn on Ambient Occlusion. 

Rest is just hit and render.