Is there a way to download the Dell Factory Image to reinstall it on an Inspiron 1545?
No -- if it has been deleted, it's gone. You must do a manual reload.
I've got an image of mine, but it's a 1735. If you want it, let me know.
BTW as far as I'm concerned, good riddance! There's too much garbage in the OEM setups anyway. It could, however be of use if you're not comfortable with making changes on your computer.