Magnetar vaporization is about the electromagnetic force (which is much stronger than gravity) tearing your molecules themselves apart. (Although the gravitational tidal forces around a magnetar would also be unpleasant.)

Magnetar vaporization would not be painful: Pain requires nerves, and your nerves would be gone. It also requires a brain to receive the nerve impulses and that would be gone too.

Spaghettification could be painful especially around a medium-sized black hole because it would happen slowly enough that you could feel your body being torn apart. Around a small black hole it would happen so fast that it would be essentially painless. Around a super-large black hole like the one at the center of our galaxy the tidal forces might be so gentle you'd never be spaghettified at all.