Hi Groobo,
Think I'm in a similar kind of boat to you ! I'm 34 and seriously considering leaving work to train full time. I work in IT on the technical side and enjoy the challenges sometimes, its a good profession for giving your grey matter a workout. I really got into IT hoping to save some money to do a PPL which I eventually did. Only afterwards did I find that I could just meet the eyesight requirements for a commercial license medical - I think the requirements changed slightly here in the UK in the last few years.
So now its a question of taking the plunge. I dont think you are too old by any means - I haven't come across too many people telling me Im a complete idiot for considering working in flying at my age ! However, I think you need to realise that it may be a bit harder than starting when you are say 25. If you want to do it and you have a positive (but realistic) attitude then you stand a good chance. As has already been said, you probably arent going to make as much money as in the IT profession. At the end of the day though, if you can make a half decent wage and do something you really enjoy then its got to be a better option than making more money and doing something you dont find all that enjoyable.
erm, hope that helps a bit.