XP OS 2 cant copy and shows error

Hello, I'm a first timer who encountered this kind of problem and i dont know what I'm going to do to bring back my computer booting procedure normally...... at first i run some software named Tune Utilities 2007 and i click clean and repair..... then i click tune up registry cleaner.... after the software scan all the datas, I seen list of errors on my pc .... the i click clean the files...... when its finished.... I accidentally shutdown my computer.... and i Restart but instead the computer will boot to windows xp..... Ive seen a some message that says (system 32\pci devices) corrupt or missing..... and because of that i feel so worried what i'm going to do.... I consult it to my friend who is an IT student in our town and he gave to me a windows XP 2 OS CD but when I load it on my it boot onmy disc drive, but after booting there another words appear on the screen and it says that it has an error on Local Disc D: ...... and then I consult it again on my friend.... and he said that I must go to a person who has some specialty about computer.... and so i go... but when he the person repair my PC he says that the CD can boot but in the middle of time when it copies the datAS ON THE CD it saids that it cant read.... but he said that his CD is clean and he used it when he repair for his some customers and he said it is the first he encountered that kind of situation.....


pls.help me who encountered this kind of situation

I hope you can solve this question