Nikon lenses, which is better?

Hi! I really want to buy a lens (for my d3100) with a big aperture to get the blurry background look or whatever. Just wondered which lens i should buy?

Nikon 35mm AF-S f/1.8 DX

or

AF NIKKOR 50mm f/1.8D

the first one is 100 more expensive so i'm assuming thats the BETTER lens but is there a huge difference between them?

Better is subjective, it matters how you use it. More expensive does not mean better. As you can see, they are two completely different lenses. One is a 35mm and the other is a 50mm. Both are good for portraits and can achieve the same effects. An even better lens would be the 50mm f/1.4 which is slightly faster then the 50mm f/1.8

The 35mm on a DX body will yield an affective focal length of 50mm, while the 50mm on DX will be closer to a 75mm (portrait) lens. The 50mm Will also not autofocus on the D3100 because it has no built in focus motor.

Nikon 55-200mm f/4-5.6G ED IF AF-S DX VR [Vibration Reduction] Nikkor Zoom Lens Dual Image Stabilization
* Capture movies in HD quality 720p resolution
* 3.0-inch high-contrast LCD and Electronic View Finder
* Track a moving subject automatically for still picture capture