Is it possible to MM FantomCoin and LiteCoin?? Or just to choose from BCN, MRO and QCN?
Litecoin is not CN coin, so just choose from available ones like you've said : BCN, MRO and QCN.
It is possible to mine both of them as they use different resources. FCN uses CPU and Litecoin uses GPU. But its meaningless as CPU will be overwhelmed.
Yes, you can do both on the same computer. For the CPU, mine FCN or another CN coin with simpleminer, minerc, or SoloMiner.
For the GPU (Litecoin), use cgminer or a similar miner. The mining app itself (such as cgminer) will use hardly any of your CPU because the mining is done on the GPU.
About 1.5 years ago, I mined BTC on the GPU and mined LTC on the CPU of the same computer...no problems.