Sorry to hear it.
As a first step, be sure to change your hotmail account password from a known clean computer. Choose a strong password that's not a word in any dictionary (foreign or domestic) and doesn't use trivial and predictable number for letter substitutions. Also be sure your password reset questions aren't weak and leveraging info someone could dig a bit and figure out.
If your web mail account is compromised, it doesn't matter whether mcafee works or not, the attacker is no longer using your computer, in all likelihood.
You may also want to consider reinstalling Windows on your computer. AV can't reliably eliminate threats it doesn't know about. And the amount of unknown out there these days is higher than ever.