Whenever I write the command "C:\Program Files\MySQL\MySQL Server 5.0\bin\mysqld" the command prompt hits back with something like this:
C:\>"C:\Program Files\MySQL\MySQL Server 5.5\bin\mysqld"
The context and privileges of the current user will take affect when you manually start the executable in this way.
You either need to make sure:
If you have the MySQL service installed you can also use
net start MySQL.
This page of the MySQL manual contains useful information for installing and running the MySQL server on windows.
Please remember that once you have 'started' the MySQL service (or service) you won't actually see anything, you will then need to use a MySQL client application to connect to the server and interact.