Hi Vivian,
> I expanded my virtual disk in vm player (Version 3) to 15 GB.
Correct!
Now you have a bigger disk but the partitions inside it still have the same size.
The simplest way to resize partitions is to use "gparted"
[ equivalent to the great Windows Partition Magic!

]
Just Download the ISO file from:
http://sourceforge.net/projects/gparted/files/gparted-live-stable/Then configure VMPlayer on GISVM to replace phisical CD/DVD to that iso file, and
boot from it!
VMWare menu: VM > Removable Devices > CD/DVD(IDE) > Settings
(use ISO image file)
Press F2 during the GISVM Boot to enter VM BIOS setup.
Goto BIOS boot menu and change the CD to the top of boot order.
Finally follow the GParted instructions to resize the sda1 partition to the maximum free size.
Please let us know if you have solved the problem.
Thank you!
Ricardo Pinho