I think the "suspend" was a feature in D6. I do not see that option in D7. As far as banning someone. The user is still active in the system, however they cannot login to the site.
The Activate/Deactivate feature in D7 is when you have "email activation" on. If the member never clicks the activation link, they will remain in "deactivated" (greyed out) status until they do. You can manually "Activate" the user instead of them clicking the email confirmation link, if you choose.
If you have any members banned or deactivated, they would show in the member controls. You can click the link from there to see all the members in that particular status.
Chris