I had success with xxcopy (
www.xxcopy.com ). It was really easy!
Download xxcopy to your windows machine.
Install a new hdd as "slave" on your windows machine. Use fdisk to create a partition large enough for your windows files on the new drive (be very careful here to make sure you are partitioning the new disk, not the old one!!). Now format this partition for windows.
Clone windows to the new hdd with xxcopy. Take out the old drive, set the new one as "Master" and "Bootable" (maybe xxcopy does this for you, I forget now). Reboot. Win98 should run as smoothly as it ever does.
If the new drive is larger than the old one, you will now have free space after the windows partition to allocate to linux partitions.
Hope this works for you.