Partition magic should do it . Formatting wont help,otherwise u need to delete the partition,create a new partition then format to accept your operating system .sounds easy dont it ? :-)
The way you do it depends on the operating system you use, for example, XP you can do this all from booting up on the o/system disk after you set your Bios to boot first from CD and second from HD0 (hard drive). With the likes of W98 its a lot more complicated. The best way to learn is experiment and ask questions on Google and acccept that you will probably make mistakes (I did) but thats the fun of it. Otherwise you could ask someone who knows how to help or pay a fortune to a computer shop :-)
Bri Dowd
April 2007