With a decent amount of on-board storage, and all of that - you can set it up to be an HTPC. Most laptops within the last 3-4 years will support 4k over HDMI. Those with a discrete GPU definitely will. If it has an integrated GPU, with intel 610 or newer - it most likely will.
You can buy a remote and an IR sensing dongle. Or go with a small handheld keyboard and touchpad.