The same as blackspawn here

. One single partition for the 40 GB HDD. I have the default folder to install programs, and a folder called "C:\Juegos" (< Games) to install games. I just need to back up everything in "C:\Documents and Settings" and a few more files (like stats of eMule, and some config files not stored there).
Before I had three partitions, but it was a mess. Now I carefully install and uninstall programs (I use Norton Clean Sweep) and it's much much better for me

.