Ubuntu 12.10 and 12.04 use the PAE Linux Kernel by default for 32bit ISOs and while you could use the mini ISO to install Ubuntu 12.04 on computers that don’t support PAE, that’s not possible in Ubuntu 12.10.
Further more, with 12.10, Xubuntu and Lubuntu no longer come with a non-PAE Linux Kernel, so by default, you can’t install any Ubuntu 12.10 flavour on computers using CPUs that lack PAE support (such as Intel Pentium M).
So here’s how to install Ubuntu 12.10 Quantal Quetzal on computers that don’t support PAE. The instructions have been tested on the default Ubuntu 12.10 ISO (with Unity), but they should work with any Ubuntu flavour like Lubuntu, Kubuntu, Xubuntu and so on and probably Linux Mint 14 as well.