I have in principal 3 big partitions on my Netbook. One Windows, one for shared files, one for Ubuntu. I recently find out (using hdparm) the the hardisk seems to have much better perfomance on the first 2/3 (~ 60MB/s) than on the last 1/3 (~ 40MB/s). I am thinking to delete the second partition and create new partitions for "swap" and / directly after Windows. Does this effort make sense?

I also wanna upgrade to 10.4/10.10 but keep the option to go back to the old system, so maybe I install ubuntu completely in a/this new partition?