@mea05key
There’s two basic factors that effect the camera’s quality:
- Size of pixels on the sensor
– Quality of the glass (lenses)
DSLRs have the advantage that they have larger sensors, and therefore for the same megapixel count, have larger pixels. This affects both the low-light capability, as well as the level of noise/detail in full-light shots.
The advantage of an interchangeable lens system, rather than a point-and-shoot is that you can (later) upgrade the lens to better glass. With a point and shoot, you’re stuck with whatever glass they ship.
The G10 has very nice glass for a point and shoot, but it doesn’t hold a candle to a $750 lens you can buy for an entry-level DSLR.
I would suggest you poke around at http://www.dpreview.com/ and look at their full-size images to see what you like. =)