MASSIVE PROBLEM

[kassah]

RE 1. ispCP is generally best installed on a freshly installed ubuntu, as for what options to select, you don't need to select any in the Ubuntu install, the instructions will install all needed components for you.
RE 3. *ALWAYS* backup. Like many of us, you're learning the lesson the hard way.

What probobly happened to your setup is that when you installed ispCP, it installed fcgi php, which may have caused problems with your existing mod_php setup (that LAMP installs by default). You either need to update your vhosts to use the fcgi or need to remove fcgi php and put mod_php back in.

As for future installs, I recommend installing in a freshly installed ubuntu with all options deslected during setup. The ispCP install instructions run your through installing everything needed for it. Although you may want openssh-server for management of the server via SSH =) (that's not included in the install, yet anyway).