How to use Partiton Editor in Ubuntu Installer
Tutorial on how to use the Ubuntu Manual Drive Partitioner (Something Else option) provided in the Ubuntu system Installer.
FAT32 tends to be a small bootup partition
NTFS is used for Windows and Windows backups
Ext4 and Btrfs are generally used for Linux systems
You'll also need a Linux Swap partition, which should be at least 1Gb, but its worth allocating more if you have enough harddrive space available.