noting on lidges remarks:
rundll and rundll32 are both microsoft windows programs that....run dll's. this is a necessary task to run ur computer. however there is also a virus that refers to itself as this it can go under any of the following names:
W32.Miroot.Worm, W32/Legemer.Worm, W32.HLLW.Sanker, PWSteal.Banpaes.D
otherwise it runs ur dll files when needed. some websites will tell you that windows 2000/xp/2003 all do not have this program but both of my computers have xp and both have had rundll on since we ordered them. If ur not certain that this file is a virus then leave it or u'll create more problems. check to make sure that the root path is C:\Windows\Rundll.exe, if its not it shouldn't be running and you probably have one of the viruses above.