Sorry it's taken a while to get back, been manic here, anyway from those details you have a 17" CRT monitor, the spec says your resolution should be 1024 x 768 at 85 Hz for best viewing, the refresh rate should be set as high as it will allow you to, 100Hz is great if you can manage this, I realise this is the direct reversal of what was suggested, but different monitors require different settings, the rule of thumb is TFT screens (flat ones) should be run at the lowest they allow, 60Hz is the usual setting available, but CRT monitors need to be on the highest setting for best results.
The reason for this is due to the technology, and CRT monitors have a flicker, LCD do not, and the flicker can be noticed depending on the circumstances, more so if the user is very sensitive to such things, epileptics especially can be set off in a seizure by not using a high refresh rate, some can physically see the flicker at lower rates, some can even become physically sick due to it, others will never notice it, but by having the setting at the highest possible setting means it's easier on the eyes for the user, and is essential for those who are affected by it, mild symptoms are headaches, upping the rate usually cures this, but epileptics are at serious risk at the lower rates, so they should always use the highest possible.
Right I apologise if I missed anything above (heads all over the place ATM), but as above I need to confirm your settings are correct, so if you can confirm the resolution settings are the same as I have given here then thats one thing off the list, next is check you have the latest driver(s) for the graphics, going by the info above
This should be the graphics driver you need, so try that.
Next
Here is the spec for what appears to be your monitor, and here is a snippet from it to check your hardware is compatible with it:-
The C71 color monitor is designed to operate with system units or video adapters that generate a video output signal that falls within the specifications below:
Maximum addressability (pels): 1280 x 1024
Maximum pixel rate (Mpels/sec): 110
Horizontal frequency (kHz): 30 - 69
Vertical frequency (Hz): 50 - 120
Then have you identified the monitor controls to physically adjust the screen ? and have you adjusted these to get the picture to be displayed correctly ?
Here is a download that is hopefully for your monitor, it may help with setting it up, but I suggest setting a restore point before running this to be safe, but I can't foresee a problem, it's just a safety net really and see if this helps set it up, let us know how you go, and most importantly if you have identified the control on the monitor to physically adjust the screen, and if they work\help.
But a quick last thought as a long shot, you mention your num lock light, often this can be enabled\disabled in the bios, so if your comfortable entering this check that out and set to disabled if possible, next take a note of the time and date on the clock, have you noticed it being wrong or slow\fast ? or is it completely wrong ?
If so your CMOS battery is probably on the way out, and that can throw some pretty funky curve balls at you, so it may be worth checking that as well, hope something here helps, otherwise the above suggestion of borrowing a monitor, and even testing your one on another system is a wise move, then it may help identify the monitor or the system being at fault, good luck.