Apochromatic Refractor: These telescopes are presently the top of the market for quality and price. The color correction in these telescopes is achieved by lenses manufactured with Fluoride glasses. The use of this material also allows to design fast focal ration refractor telescopes, something that was impossible only few years ago. However these are not first buyer telescope because the financial investment is remarkable. The typicl price for an optical tube (without mounting) is never below $2000 for aperture above 80mm that i consider as minimum for deep sky observing. Other than the price these telescopes do not suffer major drawbacks; if we want to be picky though the lack of aperture may be the real limit. It is still very difficult today make large lenses with the necessary color correction. In purchasing this telescope take also into account the delivery time, sometimes months. For astrophotographer lovers it is enough to knwo that 70-80% of the published pictures in magazines comes form apochromatic.
Quality brands are Takahashi, Astrophysics, TeleVue. Middle high quality with good price performance trade off are Vixen and Meade.
Newtonian Reflector: if you want to buy the maximum aperture for the minimum cost, this is the kind of telescope perfect for you. The Newtonian reflector features cost sometimes a fifth or even a seventh of an apochromatic with performance which are remarkable. Furthemore the Newtonian is easy to produce in quantity for large aperture and little cost. It seems the perfect choice for the amateur and i think it is. If you are strongly interested in visual astronomy this telescope is the best all around. Large aperture, small secondary mirror, low cost. So, what is the problem, if any, of this design? Well the problem is that this telescope is really bulky when in large aperture. Aside of this i cannot really think of any drawback for this telescope and i strongly recommend this design as first telescope (6" is probably the best first telescope you can buy) either in equatorial or in Altazimuth mounts. Concerning this last design, today the Dobsonian mounts are very popular allowing the implemenation of large aperture telescopes on easy to build mounts.
As conclusion, if you are very into the visual observing, the Newtonian is definitely the best all around telescope to buy.