From a command line do fdisk /dev/hda
to print the table. Make sure partition 1 is FAT32
to delete a partition, 1 for partition 1 then confirm,
to write the table and exit
to print the table
for a new partition, primary, number 1
accept the default start and end sectors..
to select a type, partition 1
for FAT32 LBA
to make it active, bootable
to write and exit
Also run the bootloader again to make sure it is working ok,
I personally use lilo on the MBR
and reboot, legs crossed etc...