Its generally accepted that oil (from the ground) isn't going to last forever and accordingly supply-demand will push prices up and increase our reliance on parts of politically unstable parts of the world.
(1) It depends on the fuel (and of course the soil and environmental conditions) - but maximum yields are currently around 4700 L/ha - but some people suggest you could get 5 times that from algal production. So to fuel a modern car to travel 10000 miles, you would need roughly 0.2-0.25 Ha of land. If you use a less efficient crop it could be 4x that, but potentially this could fall with future developments.
(2) It depends on who the person is and what they eat. A full size standard UK allotment (about 0.025 Ha) is supposed to be capable of providing all the veg a family of four require. A diet including meat would require much more space (for both the animal's welfare and growth of animal feed). This also doesn't include wheat (so no bread) or e.g. barley/hops (so no beer). Google suggests that to feed our western diets you need about 0.5 Ha of land in active production. In other parts of the world much less could be managed; of course they also use much less fuel too.
(3) I'm sure the numbers are out there. Deforestation is an issue, for some of the most "efficient" fuel sources like palm oil. But actually most palm oil goes into food production - which contradicts the simple logic you might assume from 1 and 2.
(4) It depends how you define polluting. Potentially fast growing high yield crops are better at absorbing CO2 than old forests full of slow growing trees. If deforestation would happen anyway and it is simply a matter of the "purpose" to which the land is put then growing biofuels (low or positive "greenhouse gas" effects) might be better than giant cattle ranches producing loads of methane. Certainly measuring environmental impact on a single parameter (such as "carbon") is stupid - but equally assuming that we in the 'rich west' should be able to determine what other countries do with their assets, so that they might catch up with our economic development, seems rather dumb/selfish to me.
Biofuels are potentially part of the energy solution, and there are some fuel sources emerging which are suited to growing on soils unsuitable for food production - but I think the question you have not asked is:
(5) Is an over reliance on biofuels simply moving our dependence on unstable/rogue states from one region to another?