I generally click "unsubscribe" in the email, then if I have to do more than click a big, obvious confirmation button on that page I close the tab and flag it as spam.
Fun fact: at least in the US, the CAN-SPAM law is actually pretty specific about how unsubscribe pages work. If it requires more than typing your email address and clicking a button then it is probably not compliant.
Why are they even allowed to make you type your email address? I used different email addresses for everything I sign up for so I have to go back to the email to see what I used. Very inconvenient.
