Cannot start DB system

All,

I have postgreSQL 8.0 on winXP. This morning at 7:59am, the db system could
not start.
I looked at the pg_log. Started from yesterday 1:30pm, all log files have
this line:

database system was not properly shut down; automatic recovery in progress

Then, I restarted the PC several times, I did not see any new log in pg_log
folder.
Thus, I think the db system might be crashed or cannot funtion at all. I
tried two things:

1. Go to command prompt, typed net start -pgsql8.0, I saw :

The PostgreSQL Database Server 8.0 service is starting.
The PostgreSQL Database Server 8.0 service could not be started.

The service did not report an error.

More help is available by typing NET HELPMSG 3534.

2. Go to command prompt, typed psql -h 127.0.0.1 Postgres template1, I saw :

psql: could not connect to server: Connection refused (0x0000274D/10061)
Is the server running on host "127.0.0.1" and accepting
TCP/IP connections on port 5432?

If the db system is crashed, how do I fix it ? Any help is really
appreciated.

Thanks !

Tan Chen Yee