I want to give you some more information. Based on your visitor estimates I think you do not have a lot of knowledge about it. Because for this number of visitors you do not really need a cluster.
But now to the other stuff. Yes, Windows clustering is (up to Win Server 2003 [1]) a lot easier. But this is because it is not really a cluster. The only thing you can do is having the software running on one server, then you stop it and start it on the new server. This is what Windows Cluster is doing for you. But you can not have the software running on both servers at the same time.
If you really want to have a cluster then you need probably some sort of shared storage (FibreChannel, iSCSI, etc.). Or you are going to use something like DRDB [2]. You will need something like this too if you want to have a real cluster on Windows.
I recommend you to read some more on the Linux HA website [3]. Then you get a better idea what components (shared storage, load balancer, etc.) you will need within your cluster.
If you only want high availability and not load balancing then I recommend you to not use Windows Cluster. Better set-up two VMware servers with one virtual machine and then copy a snapshot of your virtual machine every few hours over to the second machine.
[1] I don't know about Win Server 2008
[2] http://www.drbd.org/
[3] http://www.linux-ha.org/