I was wondering whether a simple reformat using the built in reset function would get rid of any potential nasty malware on my laptop or is it possible for some malware to survive it? What would I need to do to be sure my new install is completely clean (i.e. resetting BIOS, etc.)?
It's possible for malware to survive a reinstallation of Windows. This is often the case when you only wipe the Windows partition (which means that you have more than one partition on a drive, or multiple drives on your computer) and the malware hides in another one, and wait for Windows to be reinstalled in order to infect it. It also happens when the MBR is infected, which would lead to Windows being infected on every boot. The most common case of reinfection after a fresh install, is plugging in the computer an external device that is infected, like a USB flash drive or an external hard drive. So you would need to ensure that these are clean before plugging it back in the computer. There's also one known BIOS malware, but it's not really "in the wild" and only targets one specific model of BIOS, so I wouldn't worry about that. However, if you were to have an infected BIOS, the only way to clean it would be to flash it or upgrade its version (since upgrading it will flash it at the same time). As for an infected MBR or second, third, etc. partition, you would have to totally format the hard drive before reinstalling Windows on it. This can be easily done during the Windows installation by bringing up the command prompt, opening the diskpart utility and using the clean and format commands. If there's anything else that you would like to know, feel free to ask