Esc + Shift + Ctrl and Ctrl+Alt+Del Dont work

[Spec]

ok..other topic got ruined, but, my Esc + Shift + Ctrl and or my Ctrl+alt+del doesnt work either, i have no clue what is going on, it started happening when i started to use Microsoft Frontpage, ive tried to a system restore to a date and time when it did work, still nothing, any clues on what is going on? i mean, this is really wierd, im also playing a game and i want to minimize to a different program, Alt+Tab doesnt work either, also here are my system spec's
Ok Here Are My Specs:
Amd Sepron Processor 2.5 Ghz
40 Gig Interal Hard Disk
140 Gig External Gig Hard Disk
512 Ram
Asrok Motherboard
Ati 9600 Series Se Agp, 128 Bit (special Edition)
<EDIT> My OS is windows XP home edition