Yes, the principle is the same with digital SLRs- the one thing to watch out for is that the lower end dSLRs have a smaller imaging size- your 50mm when mounted to the body will be a 75mm or so lens. It's great if you want reach, but bad if you want a wide angle lens.
The photos that I took, the aperture was actually kind of high- somewhere around f/8 or so. This particular lens has a very shallow depth of field to begin with.
With dSLRs and some advanced point and shoots, you can still set the aperture and shutter speed, also ISO.