Those ones are beter?

Nikkor 50mm F/1.4 G or Nikkor 50mm F/1.8 G

The smaller the number, the smaller DOF you can achieve (blurred background, perfect for potraits).
The 1.4 is also known to be a sharper lens.

I think one thing you should keep in mind, is you will grow into the lens even if you don't feel you will "harness all it's potential" right now. The lenses will stick with you from body to body, probably lasting you a long time, and it's pretty disappointing when you realize you scrimped on quality to save some money way back when.

So, the easiest solution is to ask yourself… Can I afford the 50mm f/1.4? If yes. Get it. If no, get the 50mm f/1.8 and be happy.

Edit^^^^
Four thumbs down
Zero thumbs up
For a very informative answer.

I don't get you people, if you can give a better answer do it, just don't hide behind the anonymous thumbing down system.