hmm-m-m! . . . I need some help please

MACHINE SPECS - a home build system that has been working well since April 2011.
mobo - Gigabyte GA-770T-D3L
CPU - AMD Phenom II X2 B55 with 'stock cooler'
Memory - Extra Value 4GB DDR3 1333MHz - 1 stick
HDD - 80GB Samsung Spinpoint SP0812C sata2
GFX card - Zotac GT 430 1GB DDR3 DVI HDMI
PSU - Be Quiet BQT L7-530W Pure Power
OS - Win XPsp2
all in a CoolerMaster tower case

INITIAL PROBLEM - started with the machine reporting a ' ?###? file is missing or corrupted' (sorry, I don't recall the error code/file name) and when I tried a re-boot it failed at ...\WINDOWS\SYSTEM32\DRIVERS\WUP.SYS

MY RESPONSE - after 'scratching about' with the hardware I replaced the battery for the bios, ran Memtest86 (report was 'clean'), ran CHKDSK (report was 'clean') removed the 'original' hdd and installed a 'clean' replacement drive with a view to installing Win 7; that install attempt failed at \WINDOWS\SYSTEM32\DRIVERS\DISK.EXE

CURRENT SITUATION - I'm not sure where to go from here hence the post :confused:

Thanks for any feedback/suggestions/advice/questions :thumb:

regards,

yoyojoe