1. You need to use the following driver for connect to MS Access 2007 Database
Provider=Microsoft.ACE.OLEDB.12.0
then you can connect as follows if page and database are in same directory
conn.Open(Server.Mappath("Opportunity_Feeder.accdb"))
2. you can update any number of fields above was just an example.
to update 2 fields, you can use the following:
conn.execute("update LIST002 set field1 = " & rs("field1") & ",field2 = " & rs("field1") & " where id = " & id)