Those telescopes are not designed for people who are the discerning astronomer. A smaller scope with superior optics is a much better deal than a large one with poor quality optics or mountings. I'm not dropping any names, but a Meade or Celestron product will probably suit you much better than a Tasco or Bushnell product. The thing to look for in a telescope is aperture. Bigger is usually better.
Most images are fine to see with a modest amount of magnification.
The thing that we want is for it to be a brighter image. The reason galaxies look like smudges is that we can not take in enough of their very faint light to see much structure. We do not see many colors because our color vision is much weaker and requires much more light than our black and white vision. The numbers to look at are focal length and aperture. To determine magnification simply divide the focal length of the objective lens by the focal length of the eyepiece.