Bah i answered this in another thread
Ok...
Full Install - This installation installs every component that's included in the OS Installation disk, including all the fonts, networking components, games... etc..
Typical - Pre-defined listing of what the Manufacture believes would be a good configuration for standard desktop PC users, the install is customised by them.
Portable- This is where The installation is customised to suit Laptops, primarily based on the power settings, the power settings will be adjusted accordingly if this installation type is selected
Custom - A installation where you choose to install what you desire, based on your needs, this is mainly for advanced users, it's a good method to consume space if you don't want to waste too much space for your OS install.