I am a graphic designer at a company right now. All I can say is cooperate design is not the way to go man. You can make great money and have the security that a free lance designer does not necessarily have, but if forces you to be "creative" in a tiny box and adhere to the company standards. Don't get me wrong it can be enjoyable but freelancing gives you more freedom and creative options.
On the freelancing side getting a buisiness started can be really really tough, especially in the United States. The taxes can be ferocious if you don't know about deducting the right things. I am not sure about other countries, but here it can be rough. However, freelancing is great with all the freedoms it offers, you can also join a design firm or advertizing firm and take the work that they get in.
If you are starting out though, I would suggest becoming an intern somewhere to get that experience.
Being a graphic designer is quite fun at times if you enjoy layout, logo design, website design, working with printers/vendors, and working with people. Dabbling in Flash is also a really good idea to take into consideration for graphic design jobs. Also having a good feel for grammar, punctuation and spelling really comes in handy.
Sorry to crush your dreams on the stressful part man, this job can be uber-stressful. You can get hit with ridiculous deadlines and there is nothing you can do about it. Also working with special people whom you will never please or will jip you on money or pull out at the last second. Also those people who want you to do everything for free because you enjoy doing it and don't deserve to get paid for that. This list goes on and on with the stresses of being a graphic designer or artist for that matter. It is tough and not easy. The deadlines can really be a mean monster. However, the creative freedoms, the being your own boss(at times), and just creating something and seeing the pleasure on that person's face when you get the right design is priceless.
There are ups and downs to every job and because people are always in a rush these days there will be stress in any job you look for. It just better be a job you enjoy enough to deal with the stress.
This is a great site about all the special people you can meet while doing graphic design or freelance artwork:
Clients From Hell
I particuallrly like this one : "If we crop out the fat kid, will it knock the file size down enough?"
Ahhh.... people.....
Anyway, I hope this helps and as a designer in the industry I would be willing to offer you any other insight you may be looking for.