pagefile.sys is the swap space for information that is swapped to the harddrive out of memory. From everything that I've read, it is not necessary to "clean" this file. There are no performance gains by doing so. 384MB might be the smallest size that Windows allows this file to be. Unless you have major performance issues due to your Virtual Memory (what Windows calls the swap file) configuration, I'd leave all of that alone.
MartyMcFly commented: good suggestions, MMF +1