Please help! Need computer updated to 10.6.8 from 10.6.3

Yesterday I was troubleshooting my computer because it seemed as though someone else had remote access to my desktop. Somehow I managed to erase everything on this computer and take it back to 10.6.3. (Not sure how I managed that) I've got my files backed up on my external hard drive. However, my printer will not connect with my computer now. It is requiring 10.6.8 which is what I had before my computer was wiped clean. I;ve tried to update to 10.6.4 and 10.6.7 to be able to get back to 10.6.8 and my computer will not support the software. I am at a loss. Can someone please help me get back to where I can at least use my printer. I've tried to download software from Canon and same thing, my computer is not supporting it.

Thanks in advance. Any help is much appreciated.

Dusty Ann