The LEGO Movie Videogame

1st place I saw to do this was beside the red brick on top of the saloon in the old west.

You need to buy the dynamite throwing robot a little to the left of it, the mission marker leads you up on top of this saloon after you get to the wild west. After buying the robot climb towards the mission marker with wildstyle but follow the roof around to the right and up another ladder, you will see the computer beside the red brick.

There is only 1 enemy and the track is shaped like a figure 8 so it's easy to collect all of the studs here.

If you have the space man or other robots then they can hack also, I just pointed out the dynamite robot as he would be one of the 1st capable of hacking , and you can get this before you do level 4 or 5 with him I believe.

Also note when you collect the last stud a purple one will appear somewhere on the screen, be sure to get this one too.

Another really easy one can be found in the bonus room after the end credits.

Beside the very first puzzle, I found the one you need to solve to get the x10-red brick in Bricksburg the easiest.
You have to hack two spots but there ist only one enemy located in a very simple shape.
As stated above, don't forget to collect the purple stud that appears when every other stud is collected.

This can be attained after completing the seventh level: "Attack on Cloud Cuckoo Land".

Just follow the green stud trail a little bit to come to a computer which you can hack (Press (B) with Benny as your character).

The mini-game is simple with you having to collect all the studs whilst avoiding the opposing piece. When you collect the final Lego stud an additional purple piece will appear in the centre of the grid. Make sure to collect this and then proceed to the red button and press (B) to unlock the achievement.

*Note: This was done in Story Mode but it can also be done in Free Play mode.