How to Resize Your Ubuntu Partition
Whether you want to shrink your Ubuntu partition, enlarge it, or split it up into several partitions, you can’t do this while it’s in use. You’ll need a Ubuntu live CD or USB drive to edit your partitions.
The Ubuntu live CD includes the GParted partition editor, which can modify your partitions. GParted is a full-featured, graphical partition editor that acts as a frontend to a variety of Linux terminal commands.
Boot From CD or USB Drive
If you have the CD or USB drive you installed Ubuntu from, you can insert it into your computer and restart. If you don’t, you’ll have to create a new Ubuntu live media. You can
download an Ubuntu ISO from Ubuntu.com and burn it a disc by right-clicking the downloaded ISO file and selecting Write to Disc.
If you’d rather use a USB drive, use the Startup Disk Creator application, which comes with Ubuntu. You’ll find it in the Dash.
Provide the Startup Disk Creator application with a Ubuntu ISO and a USB flash drive and it will create a live USB drive for you.
After creating the live media, insert it into your computer and restart. If the live environment doesn’t start, you may have to enter your computer’s BIOS and change its boot order. To access the BIOS, press the key that appears on you screen while your computer boots, often Delete, F1, or F2. You can find the appropriate key in your computer’s (or motherboard’s, if you assembled your own computer) manual.
Using GParted
While the GParted partition editor isn’t present by default on an installed Ubuntu system, it is included with the Ubuntu live environment. Launch GParted from the Dash to get started.
If you have multiple hard drives in your computer, select the appropriate one from the drop-down box at the top right corner of the GParted window.
Partitions can’t be modified while they’re in use – partitions in use have a key icon next to them. If a partition is mounted, unmount it by clicking the eject button in the file manager. If you have a swap partition, the Ubuntu live environment will likely have activated it. To deactivate the swap partition, right-click it and select Swapoff.
To resize a partition, right-click it and select Resize/Move.
The easiest way to re-size a partition is by clicking and dragging the handles at either side of the bar, although you can also enter exact numbers. You can shrink any partition if it has free space.
Your changes won’t take effect immediately. Each change you make it queued, and appears in a list at the bottom of the GParted window.
Once you've shrunk a partition, you could use the unallocated space to create a new partition, if you like. To do so, right-click the unallocated space and select New. GParted will walk you through creating the partition.
If a partition has adjacent unallocated space, you can right-click it and select Resize/Move to enlarge the partition into the unallocated space.
To specify a new partition size, click and drag the sliders or enter an exact number into the boxes.
GParted shows a warning whenever you move the start sector of a partition. If you move the start sector of your Windows system partition (C:) or the Ubuntu partition containing your /boot directory – likely your primary Ubuntu partition – your operating system may fail to boot. In this case, we’re only moving the start sector of our swap partition, so we can ignore this warning. If you’re moving the start sector of your main Ubuntu partition, you’ll likely have to reinstall Grub 2 afterwards.
If your system does fail to boot, you can
consult the Ubuntu wiki for several methods of reinstalling GRUB 2. The process is different from restoring the older GRUB 1 boot loader.
Click the green check mark icon on GParted’s toolbar to apply the changes when you’re finished.
Back ups are always important. However, back ups are particularly important if you’re modifying your partitions – a problem could occur and you may lose your data. Don’t resize your partitions until you’ve backed up any important data.
After you click Apply, GParted will apply all queued changes. This may take a while, depending on the changes you make. Don’t cancel the operation or power down your computer while the operation is in progress.
Restart your system and remove the CD or USB drive after performing the operations.
This worked for Ubuntu 10.10 and is great set of instructions
http://askubuntu.com/questions/126153/how-to-resize-partitions
