I want to run a new wire fronm the service panel to serve four can ceiling lights, and four outlets inside a home. Do I use 10 gauge or 12 gauge for this and do I need two lines ran from the srvice panel with 15 or 20 amp breakers?
Craig

Wattage per breaker is voltage dependent. That's why you can use higher wattage on the same gauge wire when you have 240VAC. What will you be running on the outlets, floor lights and a TV or cooking utensils, heaters, motors etc. Nominally, on a 14 AWG you can run 1800 watts and on a 12AWG you can run 2400 watts. Never saw a regular room circuit run with a 10 unless it was for a wall AC. So, in order to give you a correct answer, we need to know what you will be running on the outlets.

Basically I am running 4 ceiling can lights on a dimmer switch, a TV set, four receptacles, and six low voltage recessed lights.

Sounds like a family room, den, etc. If so, one 20 amp circuit with #12 wire would be fine.

If the outlets would have any AC units, refrigerators, computers, etc. you may want to consider having two 20 amp circuits.

The new circuits would need to be Arc Fault protected by using a AFCI circuit breaker.

Be sure to install a smoke detector, if there is not one for that level now. It may need to be interconnected with others in the home.