psql command line

dear all,
I just installed postgreSQL 8.0 on windows xp.It seems to work well meaning i can open the Admin tool and start/stop service. But when i try to run psql command line exe file, It opens asks for password and closes. i am not able to run the command line utility. Any help would be greatly appreciated as this is the first time Iam ever working/learning on a server based database.

Kris