Okay, I'm going to take the opposite tack from Umbran and assume that the character is actually intending to stay a fighter for a while rather than immediately multiclassing. Partially just because, as he said "it should be interesting". Also, if I were choosing purely for a good 1st hit die to counteract the low Con, I'd go for barbarian- 10 hp at first, and the rage ability also help as long as the player knows when to make a tactical retreat. (ie, doesn't let himself take enough damage so that when he comes out of rage, he's dead... ^^;;
If he wants to still be combat effective as a straight fighter, I'd probably put the 17 in Dex and focus on ranged weapons and lighter armor. At first level, he'll only have 8 hit points rather than 10 or better, and it'll get worse from there. If he tries to go the route of the high-Strength tin can tank style of fighters, stuff that's at an appropriate CR will probably drop him if it hits him. Heavy, enchanted armor might be able to counter that to a point, but with a dwarf's already low movement rate, that leaves him about as ungainly as a beached aboleth- and about as easy a target.
It's not as bad as the wizard my party had with the 4 Con and the one hit point per level, but then again, the wizard wasn't expected to do anything but hang back and cast spells in the first place. As a fighter, he's going to be expected to, well, fight, and if he tries to go the melee route, he'd better have a cleric watching his back. As I said, I'd go for ranged combat, and I'd also get a mount as soon as possible. A high dex boosts his Ride skill, and the Mounted Combat and Point Blank Shot feat chains (all on the fighter bonus feat list, I might add) can make him a force to be reckoned with.
Background-wise... well, I'd leave that to the player. Whatever history they come up with is bound to fit the campaign and the character much better than my ideas... But if it were my character, hmm... I might decide to play him as a seasoned veteran of many skirmishes against whatever the local nasty hordes are (ie, orcs, gnolls, goblins, etc...). Hampered by old wounds but too strong-willed (some might just say stubborn) to simply give up and die. Not the hardiest dwarf in the world, but courageous, loyal, and perseverent to a fault, the first to rally the party in times of trouble and the last to give in.
So, what do you think, BVB?