Well the ranking amongst these depends on the specific use. However if overall consideration is given then Prado, Surf, Pajero and Rav4.........becoz
If someone thinks that Pajero is a powerful and capable Off roader, I think he is mistaken. Pajero is actually a 4WD "family wagon" and belongs to the metalled roads.
Prado has advantage of its toyota heritage and comparative capability. However prado and its predecessor "Land Cruiser II" are classified as light duty by the maker.
Surf and Prado are essentially of same capability, with same platform.
Rav4 is a wastage of money.
I dont think any of the above mentioned "trucks" can get to Babusar Pass or Burzil pass or Deosi plains which reveals their "weakness".
If you are really for "off roading" and take your truck to the above mentioned places then Landcruiser 70 series or 73 series preferably with 1HZ engine version 4200 cc diesel are best. Not even the 100 series comes closer to these ihn power and capability.