somehow iphoto was deleted from my computer.I was told that it is on my installation disc and I should reinstall the disc.My question is do I need to backup everything on my computer to a external hard drive or can I just install iphot without the installation disc deleting anything from my computer.I have an imac and im running osx leopard.


Thunderbirds are GO!
You should regularly perform a backup of your valuable files anyway, it's up to you if you need to do this now but regarding iPhoto, you can just install it without the Installation Disc deleting anything and I suggest you do it using the 3rd party app, Pacifist.

After downloading/installing Pacifist, you use it to extract iPhoto from the Install Disc.

Pacifist is an application for Mac OS X that opens up .pkg installer packages, .dmg disk images, .zip, .tar, .tar.gz, .tar.bz2, .pax, and .xar archives, and more, and lets you install individual files out of them. This is useful if you need to install just one file out of a package instead of the entire package (for example, if you deleted your Preview application and need to reinstall it, but not the whole operating system), if you experience bugs in Installer.app that mess up your symbolic links, or if you just like a little more control over the installation process. Pacifist can open some archive formats over HTTP, in case you want to download only one file from a large .zip archive without downloading the whole file. Finally, Pacifist can examine the kernel extensions installed in your system to let you see what installer installed them, and whether the installer was made by Apple or a third-party.

Download Pacifist here.