Have you tried any of the debugging tools?
From your command screen, you can enter: C:\mysql\bin> mysqld --console and it will print out to your command screen sometimes helpful messages. If it works correctly, you'll end up seeing mysqld: ready for connections Version: '4.0.14-log' socket: '' port: 3306
You can also try looking at the .err file, where mySQL writes out issues. In the main folder where you installed your stuff, you should see a subfolder called data (`C:\mysql\data' is the typical location). The .err file is in there, and you can open and view it in Notepad.
Also, you're probably running on port 3306. If no other server is running, use your command screen to enter telnet your-host-name port-number (ex: telnet localhost 3306). If you don't get a message saying 'unable to connect', something else is using that port, which could explain why your DB can't connect.
Another thing you can do is make a trace file. In your command screen, type in mysqld -V. If the returned stmt says 'debug' at the end, you can use the debugging tools created for mySQL. On this page (
http://www.mysql.com/doc/en/Making_trace_files.html) in the mySQL Manual it walks you through a couple options for doing traces.
These may not solve your problem... just a thought, and it might give you more info.