Which has better picture quality?
This is my first "pro" camera I want it cause my sister has the Nikon D3200. But I don't have that much money… I want good pictures just like hers I was wondering if the Nikon D3100 is just as good? If somebody would tell me the goods and bad's of both of these cameras it would help a lot!
What you probably mean is a consumer entry level DSLR, a Digital Single Lens Reflex camera; a real 'pro' DSLR such as the Nikon D4 costs US$ 6, 000 without lenses, whereas a D3100 with 18-55 mm kit lens sells for around US$ 600.
The D3200 is the better camera, not only because it has a lot more megapixels (24 mp vs 14 mp on D3100), but has a lot of improved features that have evolved from its predecessor, the D3100, including a better and faster image processor and better light sensitivity. Btw, more megapixels are nice but won't necessarily translate into a better picture quality.
Because of the introduction of the D3200, the price of a D3100 has dropped significantly, and the D3100 still is an outstanding entry level DSLR. So moneywise, the D3100 is very attractive at this moment, especially so for beginning photo enthusiasts. However, entry level or not, DSLRs can be complex machines, and you'll also need a basic grasp of photographic notions such as composition, shutter speed, aperture, iso sensitivity, and depth-of-field if you want better results than just a simple snapshot and avoid disappointment.
In short: both are excellent cameras, with no real drawbacks for beginning photographers. A more advanced photographer however, might find them a bit restricting. They're also less suited for photographing hi-speed sports images, because their sensitivity, autofocus and continuous shooting speed aren't in the same league as a $ 6, 000 pro camera which was designed to reliably handle all sorts of photo assignments.
For a side-by-side comparison between the D3100 and D3200, see link below.
The D3200 is an upgraded model from the D3100, but both are capable of producing excellent quality images in the right hands.
Don't think that you will automatically get shots as good as your sisters though - DSLR's take skills to use & get the best out of. IF you take the time & effort to learn about photography you can.