ActivePerl 5.8.8 is ancient code. Consider switching to a recent Strawberry Perl. Strawberry Perl comes with a complete set of compiler, linker and make (dmake), so you can install modules from CPAN out-of-the-box, like you would do on any unix system.
The current DBD::Oracle 1.28 has some problems, it needs two tiny patches (1, 2) to compile and run cleanly. Additionally, the test t/26exe_array.t fails when Test::NoWarnings is installed, this problem can safely be ignored.
Nearly all DBD::* modules need some kind of database client library to compile, and DBD::Oracle is no exception. You need at least the OCI packages, available on the Oracle setup CD / DVD. Many people report success with a recent version of Oracle Instant Client. See also the documentation of DBD::Oracle for details.
Last time I tested, DBD::ODBC was way slower than DBD::Oracle, due to the extra overhead of the ODBC manager and the ODBC driver, so I can not recommend to use DBD::ODBC to connect to Oracle. To make things even worse, Windows comes with a really ancient Oracle ODBC driver that causes a lot of trouble. You really need to update it with a recent version of Oracles own ODBC driver if you want to use DBD::ODBC to connect to Oracle.
Alexander
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Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)