I am no expert, but I have looked at a lot of photos here and by other photographers and - although there will be exceptions to prove the rule - I would say that generally a DSLR image has a higher quality to that produced by a Point and Shoot - even the more expensive ones.
I started my journey into digital photography with a good quality Canon P&S and I was very impressed with the quality of the images. But that was for everyday photography; once I started taking photos of planes with a view to acceptance here, I found I was way off the quality mark. Now I use a DSLR, and have spent time here developing my obsessionality for detail and quality
, nothing but DSLR will do. Once edited, the quality is massively superior to anything I could get with the P&S.
Forgetting A.net, if you like the idea of high quality images, get a DSLR - I can recommend the Canon 350D, with a lens as described by Phil above. Not only will you be very pleased with the quality, but a set up like that will enable you to have the quality to get photos on here should you choose, no question, with suitable editing and a bit of work. In the UK you can get that camera with a lens for well under £500 now. Not hugely more expensive than the superior non-DSLR options. The Canon cameras usually come with Photoshop Elements too, which is all you really need on the editing front (unless you want to make editing a speciality).
Good luck and all the best.