Ok i have a linux box, i have syslinux installed there. I don't have any ubuntu box, and any windows. I know how to use cp, and dd, and what you want. Now I like to try ubuntu on netbook without cdrom.
My way to create bootable pendrive which works everytime is to use syslinux:
# mount -t iso9660 -o loop,ro /image.iso /mnt/cdrom/ # mount -t vfat /dev/sdb1 /mnt/pen/ # cp -r /mnt/cdrom/* /mnt/pen/ # mv /mnt/pen/isolinux/isolinux.cfg /mnt/pen/isolinux/syslinux.cfg # mv /mnt/pen/isolinux /mnt/pen/syslinux # sync # umount /mnt/pen/ # syslinux /dev/sdb1
it is allways working, but not with ubuntu image :/