Blowing up Megaton isn't advised. Though many players opt to blow up the first town of Megaton, this isn't a great idea: you'll miss out on some major quests, handsome rewards, and your very own house. If you must blow up Megaton, do so after you've cleared the most rewarding missions.
Earning your first house. You can earn a free house in the town of Megaton, but you have to help out Sheriff Lucas first by deactivating the dormant nuclear bomb.
Skip the Work Bench add-on. You can outfit your house with items that grant new abilities. The Work Bench is a tempting option, as it allows you to construct new weapons and items from spare parts. But you can always use the free Work Bench located in the Craterside Supply Store in Megaton. Why pay for the cows when you can get the milk for free?
Get a good night's sleep to boost XP. By sleeping in a bed, you'll earn a temporary state called "Well Rested." In this state, you'll earn an experience point bonus every time you kill an enemy, complete a quest, or perform other XP-related tasks. There's a bed in your Megaton house, so no excuses!
Your robo-butler will give you purified water. The robotic butler comes standard with your house in Megaton and can dispense bottles of purified water for you. The supply is limited, but it's a nice bonus.
You can stash excess equipment at your house. Why lug around mountains of useless gear? Stash it all in the lockers or desk of your Megaton abode and return to claim it at any time.
Exploring and Questing
The Pip-Boy is your friend. Your arm-mounted computer has an awkward interface, but it's your biggest asset in the game. It tracks quests, stat points and skills, and contains a host of other useful functions. Once you get past the convoluted interface, the Pip-boy is an indispensable tool.
Master the Pip-Boy's map. The map interface in Fallout 3 is one of the game's more frustrating elements — setting (and reading) waypoints takes practice and patience. Once you learn the ins and outs of the map, though, you'll have a far easier time following your active quests and staying on-task. Take time to experiment with it early in the game.
Change the Pip-Boy's display color. Ugh — the tiny pea-green display on the Pip-Boy can give you a headache. Luckily, you can assign a more eye-friendly color by accessing the Start menu, selecting Settings, and Display Settings. We find that Amber produces the easiest-to-read Pip-Boy display, but experiment with the others to find the perfect fit for you.
Activate the Pip-Boy's light in dark areas. By holding a button (Circle on the PS3, B on the Xbox 360) for several seconds, you can activate the Pip-boy's integrated light source. This is hugely handy in the darker areas of the game, but the light will alert observant enemies.
Use quick travel to save time. Some players don't know that you can hop instantly from one location to another in Fallout 3, which saves lots of walking time. You can only 'quick travel' between previously discovered areas, so you'll still have to brave the wilderness when searching for new areas. You can access quick travel function on the Pip-Boy map — just highlight your desired destination and press X or A on your controller. You need to be outside and out of enemy range to quick travel.
Save smart, save often. Another common sense rule, but an important one. Fallout 3 is a game about consequences, and you may find that a decision you made comes back to haunt you in a big way (case in point: enraging town residents and turning them against you permanently). In these cases, it's best not to rely on the game's frequent auto-saving — make some manual saves as critical junctions so you can rewind history if need be.
Venture off the beaten path. Some of the biggest secrets in Fallout 3 have nothing to do with the main quest line. It's worth visiting every area in the game in order to meet new characters, earn new quests, and find rare new items.