As much as I love smash brothers melee, I have to comment on your little campaign here.
There are usually two types of interpretations of rules - the letter of the rule, and the spirit of the rule. Regardless of whether "multivoting" is explicitly banned or not, a reasonable adult should be able to judge that 1700 votes coming from a single IP address is an example of abusing the system to push your agenda. If a game wins with ballot stuffing but loses miserably without it, what does that say about the popularity of the game?
Personally, Half Life 2 is my favorite game of all time but I'm prepared to accept a WoW victory - I don't even like WoW but I recognize its immense popularity. However, I also recognize the relative lack of (modern) popularity of a game released 7 years ago for a long-forgotten system. I had fun playing it back then as did a whole bunch of other people. But, sorry guys, its simply not game-of-the-decade material. It may be your favorite game of all time and I respect that opinion, but its simply not capable of winning without unsavory measures to inflate the scores.
You could have won fair and square if you actually got your forum members to vote legitimately, but instead you lost miserably because you relied on a limited number of people stuffing the ballots. Instead of trying to argue silly loopholes, you should just accept that SSBM as the cult classic that it is.
Instead of screwing with the tallies for HL2 vs WoW, why not just vote for the game you like the most or not vote at all if you don't agree with either of the games? That would be a respectul response to a loss. After all - you should be happy that your game got to the final 4 at all, I would have predicted its elimination far earlier.