I've always been curious why people are so against Win 7 Starter? We have 6 netbooks in our family, 2 run XP, 1 runs Win 7 Pro, another runs Win 7 Home Premium, 1 runs Win 8.1 and one runs Win 7 Starter. The Win 7 Starter machine is perfectly capable of doing all the things the OP described wanting to do with a netbook and the only limitation we encountered was the inability to change the desktop background. That limitation can be circumvented by a 3rd party program.
The things I would be looking at, when shopping for a netbook, would be which CPU it uses, how much RAM it comes with what is the max RAM that can be installed and how much disk storage space it has.
The suggestion of getting a refurbed laptop is a good one but a netbook is lighter and more portable and may offer longer battery runtime. I use a netbook in my RV when I travel and my kids stuff them in their backpacks to carry to their college classes.