Hi,
Thank you for responding.
Here is what you want to do if I am not mistaken
2x MS619 BengQ running at 800×600 with VGA ports
3x Optoma-W402 running at 1280×800 with HDMI ports
I am not sure if you require to have sound but running 5 films simultaneously you might have an issue, you probably need to search for a solution here.
What I recommend
As the resolutions are not very high running those movies you can use the followin;
RADEON HD 7850 EYEFINITY 6
2x CAC-1102 MINI DP TO VGA ACTIVE ADAPTER
3x CAC-1153 MINI DP TO HDMI ACTIVE ADAPTER

For the mainboard and the rest it will be up to you. You require to have at least a mainboard that has 1x PCI-E 16x and a good power supply. Make sure that the VGA and HDMI cables are good.

Regards