I really like my Nikon D90. I have a 28-300 Nikon lens that is a great all purpose lens, but the 18-200 is also a good all purpose lens. The drawback to these lenses is that they are pretty heavy.
I took Candice Stringham's Oh Shoot class at Jessicasprague.com and I would highly recommend it if you do get a DSLR. She explains aperture, iso, shutter speed, etc in a way that is easy to understand and has really helped me learn to use the camera. She also gave us this site to read reviews on the various camera models and lenses.
http://www.dpreview.com/ It's a good place to go to sort through all of the mumbo jumbo. You do want to make sure that you get a model that has auto focus built into the body of the camera. If you don't then the lenses that you buy need to have auto focus built in and that makes the lenses more expensive.