Can MySQL take advantage of multiple CPUs in a single server?
Absolutely, if your operating system supports multiple CPUs, MySQL will take advantage of them. However, the performance and tuning of MySQL using multiple processors varies, depending on the operating system. For more information, please see the MySQL manual section for your specific operating system:
What permission level must I have to use the OPTIMIZE command?
Any user with INSERT privileges for a table can perform OPTIMIZE commands. If a user has only SELECT permissions, the OPTIMIZE command will not execute.