Yup - guitar strings squeak - that's the nature of the thing. I've stopped worrying about it - I like the sound of Tom Waits working the pedals on his piano, and I like the sound of Dylan's jacket buttons rattling against the back of his guitar. I've stopped worrying so much about breath noise on vocals, too.
Apparently magazines like Playboy get cosmeticians to airbrush out their models' moles and such before a shoot. Myself, I prefer the wholewheat approach to eating, the natural noise approach to recording, and the deep appreciation of every little detail approach to a woman.