Right now (yes, it will change over time), these are the following parts I like when I need to do installations. Unless you’re having a problem you DO NOT NEED TO CHANGE ANYTHING.
Router: ASUS RT-66U. This is a N900 router, has gigabit switching, 3 external antennas, has 2 usb ports for connecting a hard drive and/or printers. Also, ASUS makes the AC1750 router which is similar and supports AC (the next coming of wireless connectivity) but it’s $30 more than an already expensive router so you’d be out the door if you bought it yourself for over $200.
Cable Modem: (ONLY IF YOU ARE NOT DOING PHONE SERVICE VIA COMCAST) – Motorola makes the SB6141, about $110. I have the SB6121 which the SB6141 replaced.
DSL Modem: AT&T is famous for providing garbage Motorola modems they sell to you and then rebate back, usually. I have installed two Actiontec GT701D DSL modems, which are probably cheaper at $65 than what AT&T sells them for. They are a bit more confusing to install but worth it, garnering great reviews and stability. I do have a stash of used Motorola’s if you need a used $25 backup in a pinch though!