The most appropriate version in the production

[luoc]

Hi all,
  Could you please tell me which version is the most appropriate in the 
production? There are our several requirements :
  1. Most stable
  2. More latest
  3. Easy to upgrade
  4. Support the 500GB every day in the production (not the test).
  5. 2.2.2 or 2.6.2 and more?

Thanks for your time.

- Luo