between a laptop and a desktop machine - at least as far as the basic operation is concerned - and it sounds to me as if you would make the ideal laptop user.
You're obviously used to a computer, and operating a laptop ( or notebook - same thing as far as this question is concerned) would come very easily to you. Obviously you will have a slightly smaller screen and keyboard, but other than that everything would be just the same. Laptops are now as powerful as desktops, and every bit as capable. Connections to printer, and the internet are identical - as is the software.
Buy that laptop/notebook, I'm sure you won't regret it - after all, since when does being 66 mean that you can't use a computer as well as anyone else? My oldest client is 86, and has his own domain and website. I began teaching him computing when he was 84, and although he has taken a little while to assimilate some of the concepts involved in computing he's done wonderfully well. He uses a state-of-the-art Sony laptop on a daily basis, and travels to and fro between his homes in Lusaka and London regularly - emailing me almost daily.