Check out the sticky thread at the top of this forum for the minimum hardware requirements for an HTPC. I think you'll find that a laptop that meets this requirement isn't going to be as inexpensive as you'd like. The main thing is that you're going to need one of the latest graphics GPUs to support HD playback as well as a 2GHz dual-core processor as a bare minimum. It should also be HDCP compliant. I don't know if there are any laptops out there with an HDMI output but I'd think they'd lean more towards the high end of the price scale rather than the bargain basement laptops that are being advertised these days.
The bottom line is that you could build a better HTPC from scratch for less money than a comparable laptop would cost. You will also have more capability to upgrade the HTPC for more capabilities as your budget permits. A laptop is pretty much locked into the configuration you bought it in, with few exceptions.
The bottom line is that you could build a better HTPC from scratch for less money than a comparable laptop would cost. You will also have more capability to upgrade the HTPC for more capabilities as your budget permits. A laptop is pretty much locked into the configuration you bought it in, with few exceptions.