How to Reformat computer using a USB?

[were]

So, a couple of years ago, I did a clean install on my laptop (Windows 7 Home Premium/Sony Vaio), booting from a USB, and everything went well.

Now, I'm trying to figure out how to simply reformat it and do the same thing over again, to refresh. There's nothing tragically wrong with the laptop, it's just slow, freezes, and is generally chocked full of crap.

I'm wondering if I can just go ahead and do the reinstall windows recovery option, but instead of using discs (because my disc drive is broken), use the USB? Would that work instead?

I apologize if this question/complaint is trivial. I'm not terribly computer literate to the point of being confident that I won't screw everything up.

 

[Pauly]

Everything you need right here to do an install from usb, it even includes links to updated install media including SP1 and beyond so you wont need to do as many updates
You would want the SP1U media refresh image from the link in step 1

http://www.sevenforums.com/tutorials/219487-clean-reinstall-factory-oem-windows-7-a.html

 

[were]

Yes, I was there and already copied that ISO.

My main question is, what method do I use to format the computer in order for this to work? When I did it before, I didn't have to worry about it because there was no OS already on there, it was just empty.

 

[Pauly]

Step 6 here shows you how to use windows in built diskpart software to format and partition your drive ready for install

http://www.sevenforums.com/tutorials/324687-windows-7-installation-failure-overcome.html#post2714895

 

[gregrocker]

There isn't any reason to save any partitions so you can delete them all during the booted install and create and format New or just click Next to let the installer do it.