coax

I am trying to connect my tv with my receiver in a finished part of my house. There are 4 coax cables and 1 cat5 cable that run between the tv location and my receiver location. I understand that in order to use cat5 cable to run a hdmi signal you should use 2 cables but I only have one so now...

I have this projector and was wondering the best way for me to watch TV? I have no STB just a coax cable. Should I ask my provider to send me a STB?

Guy at Home Depot told me to squirt a glob of Noalox right in the F-connector of outside antenna, before screwing in the cable. After reasearching, I should have only used it on the threads (not the center conductor). How can I clean out the cable-end, now (up there on the roof)? It is a RG6...