I need to set up a computing environment for several moderately demanding applications - some pure processing and some data acquisition, storage and analysis. The applications include numerical weather prediction (using WRF) and 3D rendering of an entire city. There will be two separate systems, one linux one windows. My current plan is to create a "high performance computing cluster" HPCC. For the linux side I would like to use CentOS, but it may not be the best choice for scheduling compute nodes for distributed processing. I would like opinions on 1) which linux OS is best to use and 2) which windows OS is best and 3) has anyone done this entirely using remote services like those offered by Amazon? 4) any hardware suggestions? Many thanks!