Better yet, if you have Knoppix then you can use
qtparted which is much like Partition Magic. It can even resize NTFS partitions as long as you have a way of defragging the NTFS partition to make enough free space at the end of the partition. qtparted is a GUI wrapper for the parted,
ntfsresize, resize2fs, resize_reiserfs, mkfs.*, etc... I suggest Knoppix for this because qtparted is not the easiest app to install and get all of the pieces working. Knoppix already has all these tools installed and in working order, plus many times you need to be booted from an alternate boot source to perform partition changes.