The previous message is correct - you cannot under any circumstances claim Unemployment Benefit while you are attending college or re-training. The purpose of Unemployment Benefit is to cover your income while you are available and seeking employment.
In addition - it is questionable as to whether you will even be entitled to Unemployment Benefit - it depends on how long you have been employed and the nature of your contributions.
The issue concerning your voluntary redundancy package will also impact on your entitlements to Unemployment (or any other benefits). Not only your own means - but those of your partner will be taken into account in any assessments of your income and entitlements to benefits.
I would suggest you either call into your local social welfare office and ask for the Information Officer who can go your benefit options with you - or you might call the Citizens Information Phone Service (Lo-call: 1890 777 121) who can explain your options over the phone. All contact is in confidence.
Other than that - it's impossible for anyone to advise you on a board such as this without detailed information regarding your income. I would recommend you take a look through this document that explains all about Redundancy here:
You should also read through this information regarding Unemployment Benefit here:
On a final note, it is possible to re-train for another career in a number of ways that wouldn't require you to leave your evening job. For example, there are lots of courses you can attend by correspondence (i.e., Open University, Griffith College, etc.), through evening classes, through free training offered by voluntary and community organisations in your area.
Check out your options before you make any rash decisions and be committed to whatever decision you finally make. I hope this has been of assistance.