Netbooks are good for internet and light-usage, which is mostly what you've described (apart from too many windows open). One thing to keep in mind that isn't advertised much is that they don't come with an optical drive (except for a small few). Also the screens are small but not too tiny (think about playing a DS or PSP--those screens are small and yet you can focus on them). However, once you start going sub 10 inch you might start to notice your screen real estate shrinking.
As for the keyboard almost every netbook has a different one (and a different touchpad too). Some have keyboards that are 92% the size of a desktop's. Ultimately it would be best to try the keyboard and touchpad out on a netbook before buying it as they can vary in feel, ergonomics, and quality. However, with a 92% sized keyboard you'd be able to type just fine.
A good site to check out is
www.netbookreviews.net. They've got a blog system set up and short reviews on a lot of netbooks. Another good site to check out is
http://www.laptopmag.com/l/netbooks.aspx. They have much more detailed reviews on netbooks as well as some information articles.
There's a new processor that just came out, the Intel Atom N450 (Pine Trail) and pretty much every netbook that's come out recently has it. It significantly boosts battery life so if that's one of the things you're looking for I'd suggest getting a netbook with a N450. The battery life on netbooks that use it range from 7-14 hours, depending on the make and size of battery.
Anyways, that should get you started.