Convert Access Application to Mono (or other) environment

I have a small business with 10 staff, and we use an internally developed MS-Application to keep track of applications for holiday and sick leave. The application (based on VBA) is outdated and I'd like to move it to a more modern platform (Mono, Python, or other) that is portable, and not dependent on Microsoft Office. There are also two functional modifications we will make to the application at time of migration (stage II) Here's a plan: * decide on the new environment * convert to new database. Database should have security/access rights * convert all code and visual interfaces to new platform * test functional operation * ensure all existing functionality is still available * tweak any minor functional issues in the current system (its not perfect, and hopefully a new interface will do away with the usage issues in the current system) * ensure Leave Requests can be printed (as PDF) * ensure Leave Approvals can be emailed to an SMTP host * provide source code at completion of project Phase II will be to: * ensure we can email direct via SMTP, not needing MAPI/Outlook * modify leave unit of measure to be one hour - not one day as it is in current system. This will require back-calculation adjustments in database, cross-checking, changing code in forms and reports to allow for new unit of measure. * All reports should be printable PDF