Which DSLR is right for me?

I have been saving up for a camera for a long time now.
I'm not wanting to spend over $900 (including tax and the basic 18-55mm lens)
The mane purpose of the camera is to take pictures of horses.
I ride and am wanting to take some jumping shots of my friends and some pictures of horses out in the field.
I want something with a fast shutter speed so I will be able to get a good picture of a horse going over a jump.
I would like over 12mp but it doesn't need to be that high
I would also like to take videos (that feature is a must!)

Here are some cameras I like and have been considering:

http://www.henrys.com/61710-NIKON-D3100-DIGITAL-SLR-BODY.aspx
http://www.henrys.com/64741-NIKON-D5100-DIGITAL-SLR-BODY.aspx
http://www.henrys.com/63826-CANON-REBEL-T3-W-18-55-EF-S-IS-IIBLACK.aspx

Which one do you think is right for me?
And do you have any other cameras you think I would like?

Plane and simple, the d3100 is what you want! Great camera for a good price!

I have a Canon T3. I love it sosososo much. I really don't like nikon, they just don't take the picture quality I'd like to have. Canon cameras just have that ability to make beautiful pictures without editing. It has 12.2 megs, which is more than enough for good quality. Not to mention it's relatively cheap.

Nikon D 90 kit.

If you buy the D3100 and include a $120 18-55 mm lens and $199 55-200 mm lens, you will be busy for a long time, just learning how to use it and the lenses and still be under budget, with enough money to buy a handful of 4 gb memory cards.

If you buy the D5100, the sensor on that camera performs almost as well as the amazing Nikon D7000 that costs just under $1, 200, body only, but well within your budget including the Nikkor 18-55 mm lens

Here is how the sensors of those three cameras compare

http://www.dxomark.com/...nd3)/Nikon

I guess you have to ask yourself what you want, a higher performing sensor or a second lens

Any of the cameras listed will do just fine for you. At this point in time any Current DSLR you buy even the cheapest one out there will suit your needs just fine. I'd go with the cheapest.
What you have not thought of is the type of lens you will need. If you are taking pictures of horses jumping or in fields that means will be far away so you will need a lens with more zoom like a 55-200mm.
You don't need a camera with more than 12 mega pixels you'd do fine with less than 10.
Also all DSLRs have fastest enough shutter speeds.
You should also begin to learn about photography by reading on the Internet and watching YouTube videos on subjects like exposure.

Canon EOS T3 is the cheapest of all, has less AF points and isn't that fast. D3100 is a bit better due to 11 AF points, better video, while the D5100 has it even faster, more megapixels and higher maximum ISO.

You also have Canon EOS T2i and T3i, both excellent, and Pentax K-r.

Btw shop from Amazon, B&H and Adorama, they're the chepest and best.

Here's a DSLR Buying Guide - http://www.the-dslr-photographer.com/2009/11/which-dslr-to-buy/