How do i reformatt a vista e-machine?

I like to erase files and start over where its brand new
i feel like there are hidden ad wares or popups even thought my virus and adware remover software says i'm clean please help

Create a Vista Start up disk.

The Recovery Manager examines your computer and determines how many blank CDs or DVDs the disk creation process will require. The disk creation process may require up to 10 or more CD-R disks or 1-3 DVD-R or DVD+R disks.
CAUTION: The disk must be either CD-R, DVD-R, or DVD+R. Do not use CD-RW or DVD-RW disks because the Read/Write type disks will cause the creation process to fail.

Create a set of operating system Recovery disks by following the steps below.
Click Start and type Recovery in the Search field.
Select Recovery Manager , and when the wizard opens, click the Advanced options button, if available.
Select Recovery disk Creation , and follow the directions provided in the wizard.
After all the recovery disks are created, label the disks and then you will load them on your computer, that should start you over fresh.

Put your restore disc in the CD drive.. it would either be the emachine restore disc that came when you purchased the computer, or the vista disc (if you purchased it seperatly)

Put it in the computer
Restart the computer
follow the steps

Make sure when you go through the steps that you chose you want to do a "fresh install" and or "format the C: drive" .. that will delete EVERYTHING on the drive and put it to brand new.. hope this helps!