PostgreSQL 8.0 installation on Windows XP installation

I'm trying for the first time to install Postgresql-8.0 in Windows.
When I came up to the point where I was asked to make a choice between the 
installation as a service or programe. On that point I selected Program. 
Installation process was completed I have not made any changes to any of the 
files and when I wend to run the psql.exe i am getting the following error 
message
psql: could not connect to server: Connection refused (0x0000274D/10061)
        Is the server running on host "???" and accepting
        TCP/IP connections on port 5432?

Is there any ste by step installation guide to install PostgreSQL 8.0 on 
windows XP as a program. Any suggestion please help caz i am lost.