Yeah I used to do a protein rest because Papazian says he does one every time he brews. But I noticed my head retention sucked, and so I've gone to single-infusion.
And you're right that a PR is best utilized in under-modified malts, but who sells under-modified malt these days? It's just not necessary or worth it. That goes for partial or full mashes.
And by the way, there's not really much of a difference in procedures for partial or full mashing... just introduce yourself slowly to get comfortable with the idea of mashing, and then work up to a full mash. Heck you could even start by mashing just 2 pounds of grain in one of those steeping bags that comes with recipe packs. I sometimes do this if I want to make small quantities of wort for making yeast starters. It's basically the "Brew in a Bag" method you'll see mentioned on the forum.