P&S is Point and Shoot - which fits into your budget.
DSLR is Digital Single Lens Reflex - in other words, a digital version of a 35mm film camera.
Point and shoot's have built-in lenses, DSLRs have interchangeable lenses. An affordable DSLR lens that will be long enough to do wildlife is about $600, all the way up to $6000 for the lens really needed to do the job (500-600mm) (Those prices don't include $500-$1500 for the camera body). A good wildlife lens compromise is something like Canon's 400mm F5.6 lens, which is an 'affordable' $1000.
Honestly, for wildlife a $350 camera won't even come close to doing the job. Point and shoot cameras have very small sensors in relation to DSLR's which means more noise due to cramming too many Mega Pixels into too small of an area. They employ short focal length lenses who's image is cropped heavily by the small sensor. In other words, something that will fill up the frame on a point and shoot image, will be woefully small if that same image was projected onto a much larger DSLR sensor.
To put it into perspective - I shot this yesterday - a common woodpecker - about 9" tall. This was shot with a DSLR and 420mm lens from only 10 ft away (and is cropped horizontally):
This was 226mm from only 50ft away:
As you can see, even with long lenses, close proximity to the wildlife is necessary for good shots.
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Some cool cats that can use your help
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