Considering the last partition is empty, you can just delete it and resize 7 to the end of the disk with cfdisk, then use resize2fs, which will automatically take up all of the free space.
Alternatively you can just use gparted which I think will do all of this for you with a gui.
This is actually a pretty simple operation. But I still recommend you backup your important info *just in case*
Last edited by Meson; 08-19-2010 at 09:13 PM.