Simple, just select the whole drive and install the OS
--the partition editor runs once you have made a few dialog selections
Timezone or time,
partitions, use the whole drive, the partition editor should be able to delete and format any partitions that exits..
--if it fails for a windows partition, you could use the windows OS CD and delete its partition, such as the C: drive (1st drive, 1st partition), and you may want to check EFI boot issues for Linux, if you have an EFI mainboard!