I've heard this question before and have considered how I would answer... really, I'm one that believes that everything happens for a reason. No, I don't mean destiny or fate, because I don't believe in that, but I do believe that things happen because of the choices we make, and those choices greatly effect us down the road. I am the person I am today because of the choices I made and experiences I had in the past, and I'm extremely proud of who I am-- faults and all.
Given the option of using a time machine, would I go into the past and relive my life or make changes? Maybe, maybe not. I'm unsure. Like anybody else, I've had my fair share of hardships and I've made plenty mistakes. There are instances of my past where, had I chosen a different path, some parts of my current life might be changed for the better; however, there are also many good memories and experiences I have that, if I made a good choice where I had previously made a bad one, I probably wouldn't have some of those good memories or experiences.
When my duty in the Army was done, my Granny had recently taken a fall. My brother had been around that day, and when he heard her calls from the other room, he ignored her because he thought she was just doing her usual nagging. When he eventually found that she had fallen and hurt herself, he was mortified and blamed it all on himself. My Granny was hospitalized and would have made a full recovery had one of the nurses not dropped her on the hard floor and injured her further.
It was at this point that my now fiance, who I had met through the internet, bought me a ticket to visit him in Pennsylvania on the opposite side of the country. I visited, and he and his mother asked me to stay. I knew my Granny's condition. My dad warned me that she wouldn't last much longer. I made a mistake: Granny was terrified of dying, and she wanted me around. Instead of being with her, and instead of helping my brother realize it wasn't his fault, I chose to stay in PA. I thought, "Oh, they'll be alright."
They weren't. My Granny died only about two weeks later. My brother took a hard mental hit, and here I was, livin' it up with my honey. It was a big, big mistake.
But, if I had a time machine, would I go back and change things? No, no I would not. Because of my mistake, I learned many lessons. I learned to appreciate life more and I learned to pay more attention to those who loved me. I learned that I need to cherish what moments I do have. My fiance has a brain/cancer-- if I hadn't experienced the issue with my Granny, I probably wouldn't be taking the time to truly cherish what I have now, because who knows how long he could last? I learned that people depend on me, and I have responsibilities that need to be taken care of. I learned that people like my brother learn from my actions.
If I had just visited and then gone back home, I don't think my relationship would exist right now. I'd never have got into the gaming industry. I probably wouldn't be living independently. I wouldn't be the responsible person I am today.
Maybe I'm answering this question a little too seriously, but it's something I've thought about a lot. So.... if I did have a chance to relive my life- the good and the bad- then maybe I'd do it.... but I wouldn't change a thing.