Optimize MySQL Database

I need someone who is an expert in mysql & has lots of experience in optimizing mysql databases, so the site loads very fast. The web site is [login to view URL] the web site is running very, very slow, it is on a vps acct & using a lot of cpu & slowing down all the other accounts iin my vps acct. My host, hostgator says, it is a mysql db problem, the db has to be optimized, too many process going on at the same time, per the host In essence, there is this process: mysql 0 131% 5.6 /usr/sbin/mysqld --basedir=/ --datadir=/var/lib/mysql --user=mysql --log-error=/var/lib/mysql/[login to view URL] --open-files-limit=16384 --pid-file=/var/lib/mysql/[login to view URL] It is using 131% of the processing power on your server. That is why the sites are slow and that's why it is taking so long to load everything. The database that is causing this error needs to be optimized and needs to configured not to run so out of control. The store is using opencart 1.5.1.1 which is made in php I had a programmer fix the search on the web site because whenever somebody searched for something like a model # or a description it would never work. But he fixed that but when you do a search it takes forever & slows down the web site, so that could be the heart of the problem, anyway that needs to be fixed. I have attached a screenshot from my whm acct showing the cpu usage, it is changing every second & too high. Also in the admin, under System > Backup/Restore when I try & run that, I get a fatal error message: Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 81 bytes) in /home/y7hkr3t7/public_html/system/database/[login to view URL] on line 29 that needs to be fixed also. I need this project done asap, within hours if chosen for this project, so you need to make time. If you do it right & have it fixed right away, I have other projects for you. Also if you have any other ideas on seo for this site, I already am using several methods for seo but would like to hear more.