There are no "deathmatch" type options to disable anything, nor min/max tech, setting starting labs (mil/civ), boost starting cred/metal/crystal X%. You can't disable by statCountType or planetModuleRoleType, so preventing titans just won't be on the menu.
Options were asked for July 3, 2008 https://forums.sinsofasolarempire.com/317135T (The pictures were lost unfortunately.)
Other options asked for back in March 30, 2011 https://forums.sinsofasolarempire.com/407086
Options, you got the wrong game m8. You can ask, "I do not want titans with that." However, you will get them anyway and so will your enemies. To protest StarClad making Titans, do not play with them.