Easily my favourite ground vehicle, the indestructible Warthog is fantastic for zipping around in and jumping off hills, making passengers whoop. It takes a while to build up speed, but that's only realistic after all. The suspension is great. The hog doesn't have much power in reverse gear though, which is occasionally frustrating when trying to manoeuvre out of a sticky situation in a hurry.
Driving the Warthog certainly felt weird at first, but that was probably because I was following the standard 'advice' which says that you steer it by pointing the camera to where you want to go. Well, that may indeed be how it actually works, but it's definitely not the way to drive, and you don't need the little blue arrow at all. The intuitive way to steer is basically to get 'behind' the vehicle and accelerate (joystick forward), and use the other joystick to veer left or right. Once you do that, driving soon becomes easy and fun.
A lot of people complained about the 'point the camera' method, and no wonder. But the only real flaw was that anyone decided to explain the steering that way. We'd never have had all the fuss if we'd just been told the intuitive way that hopefully most of us have fallen into. Or are there actually people out there still trying to point that little blue arrow to the right place?
The inexhaustible chain-gun on the back may not be terribly accurate, but it has a heck of kick as it sends hot lead streaming out, and makes a terrific racket, all of which is excellent for atmosphere. You wouldn't want to be in the Covenants' shoes when that thing's going. If they had shoes that is. You can improve the accuracy a bit by using short bursts or even individual rounds, just like with the assault rifle.
Unfortunately you're quite vulnerable while manning the gun on a stationary hog, particularly to long-range plasma balls from Jackals (though you can potentially jump off before such a shot arrives), or from Banshee bolts that can blow you sky high. So you have to be a bit careful not to hang around gunning too long.
Spin to stabilize
If you make your Warthog go into a flat spin just before driving off a big drop, it seems to have a stabilizing influence and you can land on your wheels with no damage (though your passengers might scream). Induce the spin by swerving as you're about to fly off. A spectacular place to try out this stabilizing technique is on the cliffside hilltop in level 2; see Driving off the edge.
If you want to run an enemy over, drive slightly to one side to make them dive the other way, then swerve to intercept them. You can swing the back of the hog around if you want a wide impact area for getting multiple enemies, such as a pair of Hunters.
In serious play, trying to squash Grunts is a foolish idea as you can so easily be left with a plasma grenade stuck to the paintwork. Stay clear of them.
I still wish I could have a first-person view when in vehicles. The switch to third-person removes you from the normal intensity of experience and weakens the feeling of being Master Chief. It breaks the illusion, reminding you that you're not there after all; you're just controlling a puppet in a computer game. That's not at all welcome to escapists like myself.