How does the HiRISE camera compare to the Mars Orbiter Camera from Mars Global Surveyor?

Is mars capable to with stand life on it?

The airbags on the Mars Pathfinder seemed like a really good idea to prevent damage to the vehicle. Why weren't they used more often? (And why not use a similar design to move around with less or no friction: a rover in a ball, until it finds a perfect spot to work from, or even an inflatable balloon to relocate the rover if the wind is good or help out if the rover gets stuck? Crazy ideas.. but still..