Forza Motorsport 2

Go an entire race without hitting another car or wall, or going off the track. I recommend the Nissan speedway. It's already available once you start the game and is a simple loop. As long as you stay away from the walls, you'll be fine!

You can get this achievement on any race track with any car. You just have to go a race and not hit any cars, drive off the track, or hit any walls. [I preferred a track that only requires 2 laps, but the choice is up to you]

There is a misconception about this achievement that you have to place well in the race. You can finish the race dead last (8th place) and, as long as you cross the finish line at the end of the race, you'll unlock this achievement. That said, take your time and make sure that you don't hit anything because it doesn't matter if you win.

Use any car on any track and drive every lap without touching walls, opponents or going off the track.

Easily obtainable within the first hour of play. Personally i did this on the first race but pick a track and car you're comfortable with and learn where your braking points are to avoid collisions and you should breeze this.

Much easier to obtain if you make sure you have it on Easy difficulty with TCS, ABS and STM all on.