Lens for Nikon 5100-35 mm 1.8 or 50 mm 1.8 (AF-S) or without AF-S?

I have recently bought Nikon 5100 and I sold my kit lens of 18-55mm and bought Tamron 18-200mm Lens. Now again for bokeh effect and mostly indoor, party pic, potraits, sometime outdoor picture I wanted to but prime lens. But couldnt fix out which one for my Nikon D5100.either Nikkor 35mm 1.8 or 50 mm 1.8. And please also suggest Focus thing manual or auto. As i'm very new to DSLR. Please Suggest.

Added (1). Kindly also suggest the whole lens name: I got to know some 35mm "D" AF-S/ "G" etc in full so that I can get the correct and full lens name for my DSLR 5100.

First, only Nikon AF-S lenses will auto focus on your D5100. Manually focusing is possible but difficult since the viewfinder really isn't designed with manually focusing in mind.

Second, when choosing any lens for your D5100 you need to remember the 1.5x "crop factor" which compares a particular lens on your camera to the equivalent angle of view of a lens on a 35mm film camera or full-frame DSLR.

On a 35mm film camera or full-frame DSLR a 50mm lens is considered a "normal" lens because its angle of view approximates that of the human eye. However, on your D5100 a 50mm lens will have the equivalent angle of view of a 75mm lens on a 35mm film camera or full-frame DSLR. This makes the 50mm lens a good choice for portraits but is limiting when indoors in small spaces.

On a 35mm film camera or full-frame DSLR a 35mm lens is considered a medium wide-angle lens but on your D5100 it has the equivalent angle of view of a 52.5mm lens on a 35mm film camera or full-frame DSLR. So its considered a "normal" lens on your D5100 and is used when you want to record a scene close to how you saw it with your own eyes.

This will help you with your D5100:

http://www.nikondigitutor.com/eng/d5100/index.html

Fix lens for D5100?
- AF-S 35mm f1.8G DX
- AF-S 50mm f1.8G
- AF-S 40mm f2.8G DX (macro)
- AF-S 60mm f2.8G (macro)
- AF-S 85mm f1.8G
- AF-S 105mm f2.8G VR (macro)

But for indoor, I would suggest AF-S 35/1.8G. It will AF with your D5100, good angle of view indoor (50mm is just too narrow in 4x4 room).

edit:
To have AF you must choose an AF-S Nikkor lenses, or HSM (Sigma). For Tokina and Tamron just look for lenses that say have 'built in motor'.