Hi Norman2....like Capt Pit Bull I tend to be one of the few who urge extreme caution when this type of question comes along.
I've made a number of posts regarding this topic - have a scroll through them.
The main problem for you is discovering what being a professional pilot is really like before you commit all your time and money to it. Well, as Capt Pit Bull advises, have a look at some of the threads on professional terms and conditions to see how disgruntled a lot of us are at the moment. And I really can't see it getting any better.
Take something you love doing, then do it too much - that's the bottom line with being an airline pilot these days.
To get a taste of what I mean, and this may seem a little crazy, but try it as an experiment - when you get some time off, set your alarm for 0430, go and scrape the ice off your car, and drive for an hour. Come back, sit at your computer, start up FS2000 or whatever, and do four sectors, say Heathrow Glasgow or Heathrow Brussels and back followed by a Nice and back. Oh, and use the autopilot - but make sure you monitor the instruments constantly. Give yourself a forty minute turnround on each - but no cheating - don't leave the room. Turn the vacuum cleaner on for that authentic turnround ambience. Read a newspaper for ten minutes if you're bored. For lunch, (usually after third sector) scoff a crappy microwave meal in five minutes flat. After your fourth sector go out to the car and drive for another hour. Now your home. Repeat for five or six days. Have two days off, and start all over again.
Now that may appear a little flippant, but I can assure you, it's actually very close to the truth. In fact, it's a hell of a lot easier. Ah, I hear you say, but I'll have a Captain with me to relieve the boredom. Well, yes, if you like him/her fine, but there will be many more times when you have nothing in common, and that makes the day even harder!
You say you're sick of sitting staring at a screen all day - erm, sounds just like my job in the air.
I'm not trying to put a downer on your dreams, just trying to give you a taste of the reality of those dreams. I've trained and flown with a number of people like yourself, and the majority of them have said to me once they've been doing the job for about a year "now I understand what you were talking about".
I've said it before in other threads, but I'd use some of that money for some really good private flying if I was you.
If you still feel you have to go for it, then good luck, you'll need it.