Hopefully you are aware by now of the so-called "crop factor" that will make all your lenses act as if they were 1.5X longer focal length in terms of the angle of view. Meaning your 28mm lens isn't going to be wide any more - but it will be close to what your 50 was before. And so on.
As others say, set the "use aperture ring permitted" option (and leave it that way - no need to change it back when using modern lenses). Use M mode, set aperture using the ring, and hit the Green button to get the camera to set an appropriate shutter speed, or hold the DOF preview to see the meter reading and adjust shutter speed for yourself. Basically, with the DOF preview held, your camera wroks more or less like the K1000, expcet the viewfinder does dim as you stop down while using the preview. Oh - and do set the option to make the DOF preview use the "optical" preview, not digital, or none of what I just said will apply.
Quote: if i were to buy a 2nd auto focus dslr lens which would you recomend for an all purpose lens?
The 18-55 *is* an all-purpose lens. If you buy another lens, why not buy one that does something different? Like a telephoto zoom (50-200, 55-300, 50-135), or a true macro lens, etc?