Setting up Ubuntu Linux dual-boot partitions

Every now and then I've had to convert a new Winblows machine to dual boot Linsux. And almost each time I've had to scratch my head to come up with a configuration that works. So here it is, for posterity.

This is what I currently have:

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda5              19G  3.2G   15G  18% /
varrun               1010M   96K 1010M   1% /var/run
varlock              1010M     0 1010M   0% /var/lock
udev                 1010M  100K 1009M   1% /dev
devshm               1010M     0 1010M   0% /dev/shm
lrm                  1010M   34M  976M   4% /lib/modules/2.6.22-15-generic/volatile
/dev/sda3             935M   52M  836M   6% /boot
/dev/sda7              36G   12G   22G  36% /home
/dev/sda1             1.5G  139M  1.4G  10% /media/sda1
/dev/sda2             128G   51G   77G  40% /media/sda2

It's not perfect, but it works. For the future though, I'd like to trim it as follows. I've kept it as percentages so that disk size expansion compensates feature bloat in accordance with Murphy's Law.

Partition      % of disk       Comment              
/              3               Linux root. Current allocation was about 8%, of which only 18% (1.44%) was used
/boot          0.1             Current allocation was about 0.02%, of which 6% was used (0.0012%)
/home          30-46           Current size was about 16%. This could be expanded to save more
/media/sda2    50              this is where most of my junk lies. Windows is mounted here
/media/sda1    0.5             manufacturer set. Windows recovery partition is here