Which type of lens is better for handheld low light photography?

I'm looking for lenses for my DSLR to upgrade from my kit lens so that I can improve image quality on my trip to Disneyland, especially in low light conditions since my fastest lens is f/3.5 (18-55mm kit lens). I'm trying to decide whether it would be better to get an f/2.8 lens with image stabilization or an f/1.8 lens without image stabilization (the specific lenses are the Sigma 17-50mm f/2.8 and the Sigma 18-35mm f/1.8). I plan to use the lens without a tripod as much as I can, especially on dark rides. Would I benefit more from the image stabilization or the wider aperture? I have a Nikon D3000, so anything above ISO1600 is out of the question, and anything above ISO800 looks terrible.

There are two important aspects for shooting hand held in low light. One feature is the cameras sensor performance in low light and the other is using lenses that are f/2.8 or faster.

Here is a sample of a shot using an ISO of 3200 AND a 300 mm f/2.8 lens

Since shooting any action or sports requires shutter speeds of 1/500th second or faster, VR really is not an issue.

The only time I use VR is when I'm shooting an editorial assignment indoors and my shutter speed is lower than 1/60th of a second and I'm NOT using flash

Link the a low light action shot.

You really need to consider looking at the Nikon D3300 instead of buying a different lens. It performs very well at ISO settings of 6400.

I would think of the faster lens as a band-aid rather than a solution to your low light shooting problem. Having a camera that performs well in low light, using the noise reduction tool in Adobe Lightroom 5 will do more to reduce any noise you will get when shooting in low light.

Eventually, sure buy faster lenses, but for now, your 18-55 mm is fine if you learn how to brace yourself against sturdy objects like light poles, walls and even by practicing holding your camera like shown on Page 27 of your user manual. You need to control your breathing and gently caress your camera shutter release when taking your shots

Since f/1.8 is 1-1/3 stops faster than f/2.8 my vote is for the Sigma 18-35mm f/1.8 lens.

Yep, I'm with Edwin. Go with the fastest glass, and that's the f/1.8.

Going with a faster f/1.8 lens will allow for faster shutter speeds, which as has been noted will not only prevent camera shake, but will also prevent motion blur.

If you're not concerned with motion blur, then using an f/2.8 with vibration reduction (VR) or image stabilization (IS) or whatever your camera calls it will result in the ability to hand-hold the camera 2-3 stops longer.

So lets say you took a picture with the 50 f/1.8 and your shutter speed was 1/60th. Switching to the f/2.8 lens that was stabilized, your exposure would be f/2.8 at 1/45th since f/1.8 is a half a stop brighter than f/2.8. You could go as slow as 1/15th (2 stops) or 1/8th(3 stops) in the same lighting conditions with the same ISO. Therefore I'd go with the stabilized lens if, and only if, I wasn't concerned about motion blur.