I have a question. I was wondering if I can start the game over because I'm getting killed and I didn't know if you can replay the game because then I would know where all of the Civs, resouces ect where
I expect the mods will weigh in on this, but the short answer is no, you cannot start over and submit the second attempt as an official entry. For exactly the reasons you state ... you then have an unfair advantage of foreknowledge.
In fact, you cannot go back to a previous save and replay any move or event differently and then submit that modified gameplay as an official entry.
The mods have methods to detect such activity, so don't submit anything but a clean first play.
The only exception is a computer crash. Then you must load the most recent save and replay all moves exacty as before, even the mistakes. So you want to have your computer set to autosave every turn (default is every 4th, so this requires a tweak). Best to notfy the gamemaster via private message if you have a crash event as well.
Other than a crash, you always load the save from the end of your previous play session, so nothing is being replayed.
That said, you can play again for your own learning and enjoyment, and even post a report of that in the spoiler threads (as long as you label it as a second attempt) ... just don't upload the final save as an official entry if you have replayed any part of it (other than the crash exception).
Lots of details here
http://forums.civfanatics.com/showthread.php?p=3234461# and also more links in the most recent post in that thread.
dV