I will try to answer on your last question: QV Servers have to be installed and configured as a cluster, and IIS or QVWS with AccessPoint could be, and that is recommended, installed on third machine, apart from QVS cluster configuration. Load balancing can be configured using QMC, System->Setup->QVWSs->on the AccessPoint tab there is list with 3 possible scenarios: random, loaded document and CPU with RAM overload.
Described scenario is for QVS cluster + one IIS or QVWS server with AccessPoint. There is another configuration possible: QVS cluster + two (or more) IIS or QVWS servers with AccessPoint each + Loading Balancing Router between user web browser and AccessPoint servers. Loading Balancing Router switches requests between AccessPoint servers, while QVS loading balancing is the same as in first scenario.