About native resolution: Back in the old days (like ten years ago, heh), people used CRT monitors (big, tv-style boxes). A CRT works by scanning a beam of electrons across a phosphorus coated surface; The surface lights up as the beam hits it, and the beam scans fast enough that it looks like a picture (it scans from left to right and from top to bottom of the display, and does one line of the image at a time, moving down to each line in the image in turn) . One advantage of this older technology is that you can control how fast the beam scans, and how much information you put on the beam. Thus, you can change a CRT monitor's resolution up and down, to suit your application, with basically no visible ill effects.
Today's flat-panel monitors are different. They typically use a grid of dots (pixels) on a panel that lays on top of a light source of some kind. Each pixel on the grid can change its properties, allowing whatever color light to pass through you want, by changing the sort of electrical signal you send that pixel. They don't scan an image onto the screen like a CRT, they display it all-at-once. This technology has many benefits (thin sizes are possible, low power needed compared to CRT), but one of the drawbacks is that you can't change the number of pixels in the image (the resolution). You can send the display images that are at a different resolution, but the electronics in the display will simply scale the image so that it fits the resolution of the panel. Trouble is, this scaling almost never works out to look as good as running the display at the "native" resolution, even if the picture you are scaling is the same shape as the monitor.
One thing you might note, if you've shopped for a high-def television lately, is that a lot of the sets advertise "1080p". This relates to a scaling issue...the resolution of such displays is 1920 X 1080, which happens to be a good match for broadcast hi-def television and video sources like HD-DVD and Blu-ray disc players. Still, manufacturers spend a lot of money and effort coming up with better ways to scale images. A lot of development effort is spent on scaling DVD images to fit high-res displays, which you can see when you price "upconvert" DVD players against regular DVD players.
Going to your monitor's specs, 1024 X 768 is a very common resolution in computer displays, and I can't imagine a scenario where this resolution isn't available for your graphics card to use to drive the monitor. The 400:1 contrast ratio is pretty run-of-the-mill. I don't see anything on the readability in sunlight of this display; I would assume, as with most screens used in this application, that you will have problems with glare in the sunlight. There are some industrial displays that are made to be sunlight readable, but they tend to be very expensive. You should be able to use some of those customization skills to mitigate the glare, tho.