Barbara, get a notebook with as much memory and as big a screen as you can. Then, if you're comfortable lugging it around to do field recordings, go ahead. After all, these days, those nifty little recorders that everyone's recommending you get are nothing but small computers dedicated to doing one thing and doing it well. Then, when/if you get tired of lugging the notebook around, the little recorders will still be around in even better iterations.
Other than that, I'd stick with one of the major brands, concentrating on the features you need/want (I will admit I'm a bit sour on HP's right now, give the nasty way mine died on me a couple months ago).