This noise could be a setting within the device that could potentially be turned off, mind providing the model code of the unit? Not sure what you mean when you mention the recovery vs. export, could you provide a little more detail as to what you're trying to do? Battery duration is subject to what's running in the background so you will want to make sure nothing is running when it's not in use to maximize the time before charging.
The model number is NP300ESK-X01BR, it's a brazilian notebook. I searched about the noise and people said it's common in samsung pcs and it's coming from HD, I don't mind the noise at all but I want to make sure it's not a problem.
About the recovery, it is the ISO image of the system. It says I can restore the system to the factory standards if I get any problem and I can also backup it in a pendrive, but the size it has (28gb) don't match the size it is saying I'll need to save in the pendrive (10,8gb). I sent two pictures.
If you need more information I'll be glad to provide. Thank you again!!
Regrettably support for non-US models is very limited. We suggest reaching out to a support team in your area for further assistance. You can do so by using the following link: http://www.samsung.com/visitcountry Thanks!