Soulcalibur IV

Make a character with Start Dash A/B/C and if possible Master Impact and head to TOLS floor 11 {seems to be a good floor for achievos}. Just walk around in a clockwise movement for the whole of the timer available. Don't attack as the AI is quite happy for you to go into orbit around her. The computers attack is fairly easy to spot so I combined this with the Just Impact one as well. I was getting 500m+ (sometimes 700m) every time and 2 or 3 impacts. Watch out when close to the edge as the computer can ring you out. Just rinse and repeat. I already had 4000m on the clock when i used this method and it took about 10 goes. The timer lasts for about 5 or 6 mins.

Two pretty fast ways to do this one. Have both players make characters with Start Dash A, B, or C (preferable A) and play SPECIAL Versus Player Match. Set Battle Time to 80 and Battle Count to 5. First way, have one player run forward and the other backward. Once at the edge of the level, switch roles then repeat. Second way, Have one person run to the center of the stage, then the other person pushes up or down on the left stick. Takes time but its pretty damn fast.

The best way to do this is to boost online with 2 players/ consoles and rubber band one control stick down (and one up if both players are boosting) so the 2 players are spinning in a circle.

You can see how close you are by going to museum and hovering over the achievement.
Obviously select max rounds 5 and max time 80.
Pick one of the maps that is a circle.