New Hard Drive Help !

It seems, your Mac, or the OS X installed onto that "new HDD", is looking for wireless pointing devices, like the Magic Mouse and Magic Trackpad.
Can you use the built-in trackpad to navigate Mac OS X?
If so, can you disable or unpair those devices via System Preferences > Bluetooth?
I guess you also don't have a Mac OS X 10.7 Lion installer? If you would have one, you could perform a clean install and get rid of that **** (and other **** the seller put on there).
Perform a Clean Install of OS X Lion on Your Mac

 

Plug in a mouse!

 

Not anymore. I don't know, if Internet Recovery works with "such an old" Mac, maybe have a look for that. Otherwise you could go into an Apple Store and ask if they have Lion still hidden somewhere. Or you torrent it.

What about asking the seller of that HDD, why s/he installed a Mac OS X version, that does not allow you to use your built in pointing and input devices? S/he clearly ****ed some things up.