Nikon 50mm f/1.8 G on D5100 for indoor equine?

So i've been doing some research for a couple of hours on what lens is best for indoor equine.
Now my 55-200 f/4 well.yeah.that's no use!

Someone had quoted:
"I need f/1.8 for ISO 3200-6400 at 1/500 on my D5100. Indoor sports has to be the most expensive thing to photograph!"

The photo under neath of the horse indoor with poor light was fantastic, visible noise was there, but it didn't bother me the slightest.

***I don't want to be wasting my money on this lens if i do buy it, but as its "50mm" is it that only? so no zoom?***

There is the 85mm but that's not compatible with the d5100 :'(

***And would it shoot better videos too? or is that to do with the video quality (as some frames are completely blurred out then 1-2 frames are in focus***

Thanks! lots of research going into this!
Added (1). The zoom isnt a massive thing to me as i will be right next to the action/moving around etc
>>> Nikon 50mm f/1.8 G on D5100 for indoor equine?

First DSLR camera, what do the number behind stand for?

In regaurds to the lens. First off 18-55 mm? Then there is the f/3.5 - 5.6??? Finally come the acronyms AF-S DX VR??? I am looking at the Nikon D3200 24.2 MP CMOS Digital SLR… This is just for pleasure. Taking pictures or moving kids!
>>> First DSLR camera, what do the number behind stand for?

Is there a problem with my camera/lens?

I bought a nikon d3100 a few days ago with the afs nikor 18-55mm lens

I'm not sure if it did this before but now when i hold the shutter button to focus, it makes a little rattley click noise. Then when i release the shutter button, it does the same noise.

Any ideas?
>>> Is there a problem with my camera/lens?

Nikon D5100 bad sports photos INDOOR?

Recently got this camera (i have the kit lens and a 55-200, if that solves anything)
And i have a massive massive interest in horses, that's literally what the card will be full of, and i'm not impressed with any of the photos i've taken.
This is a fast moving sport/hobby in my mind so i cannot be standing around changing settings after every photo i've taken, i'll be missing the shots/

This is indoor, on sports mode (tried the pets mode, was worse) and the 'indoor' mode was laggy with a flash
http://tinypic.com/r/14b48qd/6

It focuses perfectly on everything around it, but usually with a sports mode theres a moving focus green thing, which is usually there on other cameras

I tried changing the shutter speed to capture it quicker but the photo was pitch black.

http://tinypic.com/r/24fwkso/6
This was with flash, because i got fustraited.

It may seem i have no idea what i'm on about but i'm new to this, and i just want to take some decent photos after paying SO much for it

Please dont just say "practice" because thats such a wide word meaning "turning the camera on and off properly"

I want to know what i'm doing wrong! Thanks!
Added (1). Thank you very much everybody.
Are there any lenses under £550 instead of a £3000 lens to help the shutter speeds?
>>> Nikon D5100 bad sports photos INDOOR?

Nikon 70-300mm f/4-5.6G?

I have a Nikon D7000. I would like to get a zoom lens. The zoom lens I am thinking is the Nikon 70-300mm f/4-5.6G. Can someone please let me know if this lens would be compatible with my Nikon D7000.
>>> Nikon 70-300mm f/4-5.6G?

My camera is saying something but i don't know what to do?

My Nikon D3100 keeps saying on the screen Memory card is locked. Slide lock to "write" position.

i'm not so sure on what to do, all i did was put the memory card back in, it was working and didn't say this until now.
>>> My camera is saying something but i don't know what to do?

What are some good cheap nikon, canon, kodak dslr cameras?

I go on tumblr alot and i wanna know some good nikon, canon, and/or kodak cameras. And where i could buy them cheap. :)
>>> What are some good cheap nikon, canon, kodak dslr cameras?

How to make my nikon d3000 focus on its own?

This probably sounds like a very stupid question but please dont make fun of me hahah. How do i set it to where the camera does the focusing, not me?
>>> How to make my nikon d3000 focus on its own?

What is an upgrade from Nikon D90?

I currently have a Nikon D90. I used to own a Canon Rebel xs, so the D90 was a good upgrade. Now I feel like I want a better camera. Also, should I consider going back to a Canon? Because lately I've been think I want a Canon. I was looking at the 5D Mark II. What is a good upgrade from a Nikon D90 for both Nikon & Canon?
>>> What is an upgrade from Nikon D90?

Looking for a new camera? - 2

I am really into photography and I am asking for a nice camera for my birthday. I was wondering what would be a good camera for about $400.It would preferably be Nikon, but anything is fine. I would like it to take HD photos if that's possible and have it take rapid fire pictures. Thank you so much!
>>> Looking for a new camera? - 2