Do stale blocks get reported by bitcoin daemon?
My question is: does the client report stale blocks which are mined into the blockchain but not part of the main chain or are they ignored and hidden from me? 


Blocks that are not part of the main chain are never reported unless you specifically ask for them.

However if you are online, new blocks can become stale blocks and you will need to be able to handle that case.


  what would I need to to with the transactions from that block?


Undo everything that happened in that block. So all of the transactions become unconfirmed and go back to the mempool. Any UTXOs that were spent become unspent and re-enter the UTXO set.