|To start with, 320GB is the advertised capacity as rated by the HDD manufacturer when using 1000 as the base. The true capacity is based on 1024. So basically, the true capacity is approx 93% of the advertised. In other words, your 320GB HDD is actually closer to 298GB.|
PQSEVICE (probably PQSERVICE?) is a hidden partition that contains the files necessary to reinstall Windows using the ACER restore discs. If you wipe it out, you'll no longer be able to reinstall Windows, at least not with the ACER discs.