Most apps can't run from the SD card. Of those that can, most can only have parts moved. Since each part has to leave a pointer in internal storage pointing to where it is on the card, you don't save much space.
As far as rooting, we'd need to know the date of the kernel. That's one of those "orphan" phones (no information available about it, very few of them, so no one writes specific root programs for them), so it has to be a kernel exploit root.