If you are going to install another OS on the same hardrive and you only have one partition which fills the whole harddrive, then you can use FIPS to split the partition in half or however you want to split it. First you want to boot into safe mode in windows and run defrag. This will put everything at the beginning of the drive(I think). Then you can just run FIPS and split the partition to make room for whatever OS you want to install. FIPS preserves the data on the existing partion. You can obtain FIPS here: http://www.igd.fhg.de/~aschaefe/fips/