|MadSci Network: Astronomy|
Richard, as you're probably aware, the aperture of a telescope affects its light-gathering power. The bigger the aperture, the more light gathered and the fainter the objects you can see or photograph.
Now, since you say you live in the suburbs, I assume you mean there is good sky visibility (good seeing) but you still have some light pollution from the nearby city. If there is a lot of industrial pollution in the atmosphere, that can also affect your seeing.
Normally, a 6" reflector should let you see objects of about 13th magnitude. In a light-polluted area you might get a little less. But an 8" would only get you under a magnitude more. So unless you want to jump right in with something really big, my advice would be to spend your money on a high-quality 6" with features you're likely to want and use, instead of a low-quality 8".
Here's a British website with some basic advice on telescope selection:
Try the links in the MadSci Library for more information on Astronomy.