video card replaced, machine will only boot to safe mode

I was experiencing some video card issues earlier this week and posted a
question about a modern video card working on an older system. The basic
problems were

black vertical lines all over the screen and then windows 98 hangs
during posting the bios text was alternating colors blue grey blue grey and
shimmering
pc would sometimes boot to normal mode but then the black lines and it hung.
in safe mode it would get blue vertical lines about 1/2" apart but worked.
Even the screen saver came on.

The system is
ALI Aladdin V is the chipset.
MS6261 socket7 mainboard 100mhz made by Matsonic
AMD K6III +3d 400mhz
Asound sound card
voodoo 3000 agp with tvout
17.5 gig WD 5200rpm ata33
10/100 nic (provided by my isp not sure what it is)

So today I pulled out the voodoo thinking it was my problem and switched it
with a gf2 pro that my friend gave me. I got it booted up into normal mode
and downloaded and installed the gf drivers. Then rebooted and started to
clean up my desk top by moving around some icons when the pc hung. I
unpluged my monitor (referb sony 17in trinitron) and switched it for my mums
15in daytek just to see what would happen at which time the pc booted into
normal mode and hung. So I was depressed and hooked up my sony again and
went to boot up again but this time computer wouldn't boot. Its going
through the posting process fine but when its about to load windows I get an
error that says "Windows Protection Error" and something about needing to
reboot press any key.

So I did some research and found a MS page that explains alot of things to
try in safe mode.
http://support.microsoft.com/default...b;EN-US;188867
i've tried about 3/4 of the page and frustration set in so i'm taking a
break to post this huge long question.

Earlier this month my HD was lagging after downloading larger files.
Programs would lag and eventually things would freez up. After all that
happened for a few weeks I started to get the video card issues. So now my
question.

Whats wrong with my mahcine... could it be the HD is finally gone ? I'm
just about ready to replace it but before I send a few bucks on a new drive
I wanted some opinions. I'm trying to salvage this pc until the spring when
I can afford an upgrade. Any help on this issue would be greatly
appreciated.

thanks for reading
-hh