A few thoughts.
1. You have to go with either 2 RBs or an RB and a WR in the first two rounds. Trying to leave RBs until the 3rd round will probably mean you end up with real question marks at starter, so a RB in the first two rounds is an absolute prerequisite.
2. As far as I can see, there are only 7 surefire stud RBs for 2004 (Holmes, LT, Portis, Lewis, Green, McAllister, Alexander). Taking anyone other than one of these guys with a top 7 pick or when any of them are available would be a big mistake.
3. After the top 7 RBs are off the board, there is a group of another 5 RBs that are more second tier, with big question marks around them (Williams, James, Faulk, Taylor, S.Davis). When you get to this point in the draft, it's a little more of a difficult call, and depends on how risk averse you are. If you are a RB-hoard, go for one of the backs, but if you are risk averse, you can't really go wrong with one of the top WRs (Moss, Harrison, Holt and Owens).
4. Beyond the 12 RBs I've listed, it's all really a crapshoot with major question marks and unproven players. At that point, I would take any of the top 4 WRs before reaching for a RB.
5. If they are still there, Manning, Vick or Culpepper could be worth taking in the 3rd round, especially if all of the true #1 WRs are off the board. Otherwise, I would wait until the 5th round or later to take a QB because they are too inconsistent year to year, and the position is so deep that there isn't a huge difference between the 15th best QB and the 5th best QB in overall fantasy points.
6. I agree that kickers should be taken the last round because it is all a crapshoot with kickers. Consider that both Wilkins and Vanderjagt were out of the top 10 kickers last year, and that Martin Gramatica was a consensus top 5 K this year and totally bombed. It is almost impossible to predict who will lead the league in kicking points in any given year, so you may as well just take the 12th available kicker and use the extra picks on RB sleepers that could come up huge.