Its a laptop right? What graphics does it use?
Intel GMA or something like VIA? Maya isn't supported on those graphics, so it could be the cause, although I doubt it.
I noticed that you use Windows Vista... try disabling the 3D effects (actually, try disabling one at a time too see which one), I think its the transparency effects thats behind this.
C. P. U. Its not a big processor... Its a series of pipes!