Ten GB is far too small to allot to a Windows installation. The base operating system takes up most of the space already, before you install any additional software or data. The best solution, if you must use Windows, is to backup, repartition, and start over from scratch, allocating Windows a reasonable (in Windows terms) amount of space--at least 40 GB (Yes, I am pulling this out of thin air, but it's thin air with a lot of Windows experience) unless you plan on doing heavy-duty graphics and media stuff, in which case much much more.
One way to improve space in the short term would be to move the Windows pagefile.sys to another drive (partition), if you have one available to Windows. The details of how to do this depend on the version of Windows, but this will give you the idea: http://superuser.com/questions/23781...-disk-location