Modem/Router combo units vs. stand-alone modem + router?

I'm switching from AT&T U-verse to Comcast since comcast can offer speeds up to 5x faster.

As you might know At&T uses ethernet as incoming signal vs. Comcast that uses 75 ohm cable.

I need to buy a new modem and router to install the new Comcast service.

I have two questions:

1) What is better? the combo modem/router units (i.e. Motorola SBG6580) or buying a separate stand-alone modem Motorola 6141 modem + Netgear N750 wireless router)?

2) I do have one issue to overcome. I have one TV in my house that is wired for cable only. That is, it has a cable run going to it. It's too difficult for me to install an ethernet run to it, so I'm stuck having to use the cable run. Are there modem/routers that have a cable OUT so that i can feed this TV its hard-wired signal?

Thanks,
bob