What sort of server do you run? Is this a shared hosting server or are you the only user of it? I'd personally go for FastCGI assuming you have a fair amount of RAM. (FastCGI and suPHP will offer the best overall security, but suPHP will be a bit slower.)
Yes, its a shared hosting server and FastCGI is enabled.
Then leave as is. That's the best all around solution for performance / security. I mean there's LiteSpeed if you're interested in going that route, but for Apache I would stick with FastCGI.
Forgot to mention that running mod_php is a bad, bad idea in a shared hosting environment. The PHP processes are executed as the web server (nobody or httpd) whereas with suPHP or FastCGI they are executed as the individual user.
I reccomend suphp all the way. Apache fastcgi is good too but has some inherit problems.
Best way i can explain it as far as security is - mod_php is great for a dedicated server running one site and is secure if your permissions are. For shared server it is kinda more secure for the user but not the server as a whole. For example if a hacker gets a php shell on a site running mod_php then he can only write to things that are world writable or owned as nobody so that is not much on a basic site setup. With mod_php on a shared server he can cat /etc/passwd and do kind of like a brute force on common file names to read config files then connect to user's mysql or find all world writable directories. Can be done whether open base dir is on or not. And also tracking abuse is much harder with mod_php as it runs as same user as server.
With php running as user in any way such as *cgi or suphp then when a hacker gets php shell on a site they might as well have logged in ftp as the user, they would be under php as the user and would have all permissions to the user files, everything can be changed or deleted.