SQL Logins And Web Access

I have created 2 SQL logins for use in connecting to an SQL server database (v7) from my web server. My idea is that one login (WebAdmin) would be assigned the db_owner role and one login (WebPublic) db_datareader and db_datawriter roles.

However, I have run into a problem. Only one of the logins works. The other generates an "Invalid object name" error. The login that works is the login that is listed as the owner in the SQL Server Enterpise Manager Tables pane. Even if the other login has a db_owner role in the user properties box.

Can anyone tell me what is going on?

My code looks something like this:

<%
Set CN=Server.CreateObject("ADODB.Connection")

CN.Open "Driver={SQL Server};SERVER=<ip address>;UID=<either WebAdmin or WebPublic>;PWD=<appropriate password>

Response.Write "Connection Opened!<BR>"
[this part works in both cases]

Set RS=Server.CreateObject("ADODB.Recordset")
RS.Open "Select * from map_gallery_primary_geographies", CN,3, 3

[this generates the "Invalid object name" error for the login that is not listed as owner in the Enterprise Manager]

Response.Write "Value of the first field's record: " & RS(0)