What is a nice clear lens for the nikon?

I have a nikon d5000 and I want a nice clear lens that's affordable

and I want to know which you would recommend for like short films and portraits

Portraits:
50mm f/1.8 AF. Won't autofocus on the D5000. Very good quality and only costs $125.
35mm f/1.8 AF-S. Fully functional on the D5000. Very good quality and costs $200. Considered short for a portrait lens, but for 1/2 or full body shots it works well. Tight shots, better to use the 50mm.

Video:
18-105 kit lens for cheap $. I'm guessing you want zoom for videos.
Any other decent zoom will cost over $400.
If you want to shoot video for shorts, better to use a dedicated camcorder. So much easier, especially if you use a remote mic or multiple mics.