dokk2 :
Can't you just format it...???
Definitely do NOT do this.
First, Format will completely erase your disk and you lose it all! (Yeah, I know, it's all there but inaccessible because the Root directory and allocation tables are blanked out, but recovering from that is real trouble!)
But even before that a Format cannot change anything about the size of a partition. All it can do is make the existing partition blank. The suggestion to look up Gparted for free use in VISTA is the best one here.