said by MXB: I got about 300KB free on my C drive sometimes. Yes. KB.
Time to scrounge something better - a 286-based machine perhaps.
I'm sure that you can find a better machine for free. Put a Wanted ad on Craigslist or Kijiji - "Don't dump your old computer in the landfill. Looking for donation of working 3-5 year old computer. Grateful for any offers." or "Times are tough. Looking for donation of working 3-5 year old computer. Grateful for any offers."
An ad like that ought to get you something WAAAAY better than what you have now. Just make sure it has Windows installed on it and has the Microsoft license sticker on the bottom.