On the megapixel issue, really, you only need higher than about 8mp if you intend to showcase your photos on anything printed out a larger size than A4 as a general rule - I have an 8mp canon DSLR that have owned for about 6 years now and is still fantastic and have no need to trade up from for what I use it for.
Unfortunately retailers selling cameras in effect tricked consumers into thinking mp's are all important when it is more important to have:
Decent brand
Sensor quality
Optical not digital zoom (optical is physical movement of the lens to zoom whereas digital zoom is literally zooming in on the picture thus reducing the number of active pixels - avoid any digital zoom reliant cameras)
Brand wise, Canon and Nikon are very much up there as category leaders as they have huge investment and history in the category - Sony are ok although they are literally just the old Pentax brand that they purchased and rebranded, Panasonic are very much market leaders in innovation so you get great stuff from them also.
Oh and invest in a decent little read on taking photos, spending an hour or so learning the basics will transform the quality of pictures you take
Also, think about investing in some decent software on your computer, one of the major advantages of digital photography is that its now easy for your average consumer to do the 'dark room' stuff and tinker with the shots to adjust for colour, exposure etc - I got photoshop elements but there are some good free bits of software out there for basic touching up.