I love Internet Explorer, but running the 32-bit version wide open scares me just a little.Does anyone have any best practices, or descriptions of what most of the security settings mean? I'd like to lock it down--but still run at a usuable state.

To start with, make sure that Internet Explorer is running in Protected mode, i.e. do not turn off User Account Control or make sure to run IE with a standard user account. Ensuring this makes the browsing experience much much more secure than running without protected mode with an administrator account. You can always fine tune the security settings by going to Tools > Internet options > Security > Custom level.