To save some time please use this links which will have advanced descriptions that might be able to help you.
In my honest opinion i would use PLESK for shared hosting accounts as it easier to use and disable domains that use your service.
I would use CPANEL for dedicated / semi-dedicated packages as this gives the user more control than plesk does and it loads much faster.
Let me know if you need any help.
Hastings Hosts - Reseller & Shared Hosting at Low, Low Prices.