Into the future

I think people who have been following Stephen Hawking's programme of late have started pondering about the possibility of travel within the time - into the future.
I noticed some blogs today about the same and I couldn't really understand much.
In theory, looks like Hawking said it could be possible, with some "if"s to go into future, provided some time machine like thing could travel with the speed of light.I wish I could atleast understand 0.01% of it. With my little brain, I was thinking that even if someone travels with speed of light, and considering that is future? (still can't understand how it would be future), rest of the world is still in the present, right? (Yeah i am actually scratching my head now, thinking about this)..so if everyone else is in present, how could we say someone went into future. Nothing really happens there if you are the only one in there? (tapping my head now).
Someone else drew an anology that sun , is several light years away from us, and the sunrays reach here after about 8 mins. So, my little brain thinks, that should that mean that present for us is past @ sun? Well it took sometime though. (banging my head now)
Darn..can't understand..and yeah it is 1AM and it is a week day. I felt as if I understood sometime back...now I can't...relativity...nah..insanity at this time.
Phew.