Here you can edit which options the voters have for each choice you give them. By default, yes, no, maybe and rather not are always enabled, but you can disable or change any of these. You should have at least one value in this list for the voting to make sense.
Weights are factors on how the total score for a choice is calculated. These values are normally somewhere between 0 and 1. The total score is displayed both as a percentage and as the weight sum, so you are allowed to use other values if you want them to "cancel out".