Full Format with Window 7

Why exactly do you want to a full format? In most cases a quick format is sufficient and takes a lot less time...

you have to choose advanced, drop partition, re-create and reformat.

I was kind of shocked as well when the windows installer only did quick formats, but hey whatever works I guess.

i got alot of viruses and to have a peace of mind i want to do a full format xD

I think that if you choose

repair your computer -> command prompt

then type format C: it will work

If you installed your OS on another drive like D: or E:, be sure to type that specific partition instead of C: so it will completely eliminate the OS and everything attached to it.
If you want to format all of your partitions this will work too, but you'll have to repeat it for each partition.
Now if you want to delete all partitions and create new ones i'm not sure how to do it with a Windows 7 CD.
Hope this helps :]