For MySQL, I'd use mysqldump cmd; this avoids issue when the exact version of MySQL may differ (including patches).
Then take a backup of any important cfg files. Depending on your current system, these will probably not work exactly as is on Centos, but they will show you want you need to enable.
Generally, when you install Centos, it'll ask you what you want installed during that process (see Custom install iirc).
Otherwise, after it's installed you have 2 choices;
1. if you installled the GUI, use the Add/Remove SW menu option
2. if no GUI, login to an xterm and use the 'yum' cmd.
You'll want the Deployment manual
http://www.linuxtopia.org/online_boo...ion/index.html, which is a really good HOWTO/explanation manual.