My Step Two above will help you mate but to clarify:
1. Sync your trophies to PSN.
2. Disable the wifi connection on the old PS3.
3. Switch off.
4. Connect PS3 Old to PS3 Slim via a network cable.
5. Switch on both machines.
6. Tell PS3 Old to transfer to other system.
7. Tell PS3 Slim to transfer from other system.
8. Go and get a beer as this will take some time depending on the amount of stuff to transfer.
1. This will go more smoothly if you have both machines connected at the same time to the one TV. You can just switch between the channels to view the steps your taking.
2. All content on the old will be copied to the new.
3. All protected content will be transfered permanently to the new and deleted from the old.
Does that help a little.?