Since you will sooner or later upgrade your linux or change distro, maybe "my trick" will save you some trouble:
- make 2 partitions EXACTLY the same size (not one byte difference!), like 8G.
when your install is working good, go to single user mode and use dd command to copy the one partition over the other.
mount the backup, swap partitions in /etc/fstab, install backup partition in grub. now you are ready for any
software troubles that might come.
- make the larger chunk of your disk, like 23G a "data only" partition, like /export or /opt or /data.
- do have the home dirs on the OS partition, not the data partition: migration of KDE settings from one version
to another is mostly always pain. (don't know about Gnome)
better, symlink a /export/myname to /home/myname/data, and your data will survive a new distro or version.