For some years computers (desktop and laptops) do not come with recovery discs. The recovery information is in a hidden partition in the HDD. Buyers are supposed to burn these discs righ right after the purchase but rarely they do.
If you can go into Windows (safe mode or normally) you can restore the computer to factory state. In the Start Menu there is a Acer folder that has Acer Management (or something like that). Run this app and it will let you create recovery discs and also restore your computer.
If you cannot log into Windows, you can call Acer and buy the recovery disc. OR use a generic Windows disc (so long it matches the version printed on the Microsoft sticker on the you computer). The MS sticker has the cd key for the OS version that came with the computer. After installing Windows you need to install ALL the drivers for this model. Download the drivers from Acer website. There is always a change that something will be missing, an ! mark in Device Manager.
It is a lot easier to just buy the CDs. Saves more time.