Steve... This "peanut" would politely suggest you replace your power supply... 9 chances out of 10 you'll be back up an running quickly. PSUs are the most common thing to fail in PCs... Mostly because the OEMs use cheap ones to begin with; so you're not alone. This happens to most of us sooner or later.
I have had great success with the "Sparkle" PSU units I have bought from Newegg. Yeah, I know... stupid name, but darn good power supplies that are actually better than their specs say... which is just the opposite of most brands. These are sold under a number of different names, such as "Fortran Source" and others, for a lot more money. I have prolly installed over 100 of these in the last 5 years, and NONE have failed yet.
This 350 watt unit is the one I use most:
http://www.newegg.com/Product/Product.a ... 6817103011
But any of their higher rated ones will be good bets:
http://www.newegg.com/Product/ProductLi ... le&Ntk=all
You prolly want at least a 300 watt PSU, If you are going to run a lot of drives and accessories. Once you are up and running you can consider whether to buy an new PC and add your old HD as a secondary slave drive... Or just transfer your files and keep the old PC as a backup.
Best of luck... and by the way: Newegg.com Rocks!
friend ~ Brick