Conserve ammunition, and make sure to use V.A.T.S. It's the most accurate way of hitting an enemy from long range. Look at the percentage of a chance that you can hit an area too. If it's too low (below 25%) don't even bother. If you can't get a headshot on what you're aiming for, shoot the biggest target on it - the chest.
Look in all boxes an things for ammo, and repair weapons you have. To repair weapons, just find another of the same weapon - a second 10mm Pistol, for example. Go to the better one, and press Y (Triangle on PS3). Click the other 10mm Pistol. Repaired.
Also, it's an RPG game. Take it slowly, and level up intelligently. Don't go adding useless perks to your character - use only the decent perks, ones that you need. The skills have good names though - you can work out what each skill does. Read the info given about each skill, and decide if they're worthwhile.
The manual explains a lot about the game's skills too. Read it - it's big, but you'll know a lot more about the game. If all that fails, look on Google for 'Fallout Wiki'. The one on Wikia has an amazing amount of info.
The music isn't great in the game, if you don't enjoy that sort of music. If you're on 360, you can stream music from your PC to it. Put it on a low volume, and then you can play the game with whatever music you have. Alternatively, just turn the Pip-Boy's radio off.