So I've read that formatting a harddrive doesn't "delete" the files but it kinda hides them away. So for example:
Let's say I download a few programs (MSN, VLC, SKYPE, WINRAR) etc etc, I install those programs, I then choose to format my HDD which doesn't "delete" them but hides them untill they're overwritten the next time. So if I were to download and install the exact same programs as mentioned above, those would simply overwrite the same previous programs I had downloaded and installed previously correct? (this is just my theory, I'm still new to it)
So if I wanted a "fresh" start on my HDD, would a 5-6 hours format simply do it, or would the utility Eraser be a better choice?
if you want a "fresh" start your windows format tool while picking where you want the operating system installed will do the work. formatting wipes the data off the drive, it can be accessed if you try hard enough with specialized tools but I doubt you have such high value data
here are more disk formatting tools you can read about http://www.ehow.com/list_6687806_hard-disk-format-tools...
it will not over write the data untill it needs that space on the hdd after a quick format. a full format actually runs a pass over the whole hdd writing 1s and 0s. so if you were to download the same programs again there is no really way of knowing if its over writing in those exact same sectors etc (quick format). but honestly you can run a full format, there is no need for doing multiple passes on a hdd with no real important data, that also takes a really really long time