Use smartctl to check the disk state.. you can use smartctl flags to read disk sectors and write zero on it's bad sectors.. I fixed my external hard disk this way and it's working now properly
Yes you can change it to it's default
you can first check the name of your interface in your kernel log by using the following command:
dmesg | grep wlan0
dmesg | grep eth0
To change it to it's default
1. open the "/etc/default/grub" file with your editor.
2. find the line including...