Access 97 DB to Postgres Migration Questions

Have an Access 97 database being migrated to Postgres 7.3.3. Access 97 clients
will query and write to the Postgres database across a WAN via ODBC.

A few questions:

1) How does one pass a record from Access 97 to a Postgres function with a
record parameter. Postgres side seems easy enough; a table parameter.
Intention is to create functions for insert, update and delete operations
that Access 97 would call, simply passing the record as an argument. The
function would perform the necessary validation and DML.
2) Is an ODBC type conversion table available for Access to Postgres?
3) Is an SQL error table available for Postgres; would like to return SQL
error-codes and error-text from aforementioned functions and some triggers.
No need to reinvent the wheel.
4) Is it possible to grant privileges on a Postgres function?
5) Any recommended backup software that can archive an on-line Postgres
database similar to the big guys' commercial DB products and MySQL?
6) How does one capture a RAISE EXECPTION to a function return value?

Lastly any caveats or recommendations from those with previous Access 97 /
Postgres experience would be greatly appreciated.

Thanks in advance

Raymond