Partitions suddenly appeared.

My Dell computer, using Win XP-Pro, had the usual drives A,C,D,E,&F. D&E are CD Roms, F was my memory stick (when installed). I just noticed I now have F&G as "Storage Volumes" and my memory stick is now drive H. These storage devices have many files, none of which seem to be also on drive C. I never created any partitions on C, Dell Help Chat seems to think they are coming from my USB devices, which are my HP printer and my Netgear Router/Speedstream DSL modem. Does anyone know (1) where they came from? (2) can I safely remove these partitions and their files. I assumed this a software problem but it could be hardware as well.