Troubleshooting - Http://localhost error

Hello to all the asp gurus around here.....
Heres my problem.. Im running Win XP pro with SP2, I just install IIS 5.1 because im trying to preview an unsuscribe page I just create using asp. When i test the default web site with localhost or 127.0.0.1 I get an error thats says "Server Application Error-The server has encountered an error while loading an application during the processing of your request. Please refer to the event log ....."

I check the log an it states:

#Software: Microsoft Internet Information Services 5.1
#Version: 1.0
#Date: 2008-04-23 04:19:17
#Fields: time c-ip cs-method cs-uri-stem sc-status
04:19:17 127.0.0.1 GET /iisstart.asp 500
04:20:02 127.0.0.1 GET /iisstart.asp 500
04:22:13 127.0.0.1 GET /iisstart.asp 500
04:22:16 127.0.0.1 GET /iisstart.asp 500
04:26:21 127.0.0.1 GET /iisstart.asp 500
04:26:24 127.0.0.1 GET /iisstart.asp 500
04:26:30 127.0.0.1 GET /iisstart.asp 500
04:27:23 127.0.0.1 GET /localstart.asp 401
04:27:30 127.0.0.1 GET /favicon.ico 404
04:27:31 127.0.0.1 GET /iisstart.asp 500
04:28:31 127.0.0.1 GET /iisstart.asp 500
04:34:54 127.0.0.1 GET /iisstart.asp 500
04:35:03 127.0.0.1 GET /iisstart.asp 500
04:35:36 127.0.0.1 GET /iisstart.asp 500
04:42:18 127.0.0.1 GET /iisstart.asp 500
04:42:21 127.0.0.1 GET /iisstart.asp 500
#Software: Microsoft Internet Information Services 5.1
#Version: 1.0
#Date: 2008-04-23 04:49:54
#Fields: time c-ip cs-method cs-uri-stem sc-status
04:49:54 127.0.0.1 GET /iisstart.asp 500

Im not a developer but I have crate some dynamic pages using php and js and they worked perfectly.. this asp page is driving me nuts..
Can somebody please point me in the right direction and tell me what I need to do to the iis to make it work???