Welcome to the forum!
A new SSD
will be blank - it will have nothing on it. You can buy an SSD
from MyDigitalDiscount - be sure that any SSD
you buy says explicitly that it is for the Mini 9, Inspiron 910 or Vostro A90. Any other will not work.
When you get a new SSD
, you will need to install an OS. If you have the Dell Restore CD that came with your Mini you can use a USB CD/DVD reader to reinstall the OS. Another possibility is to download a free Linux distribution that can be installed from a USB flash drive.
Many people have bought chargers on eBay.