I run LMCE on my hp dv9033 laptop. It has Intel Centrino Core Duo T5500 (1.66GHz) CPU's and 2 GB of ram. It uses the Nvidia 7300GO with 256MB dedicated. I use this as my portable core for music and videos. I also use it to test new releases of LMCE. It work flawlessly with LMCE and UI2 with alpha blending. You might have issues with your version of the nvidia card. But the latest nvidia driver resolves these I beleive. (Search forums for Enable VSYNC) My laptop has 2 HDD's SATA 100GB. Something you may want to know is if you use the DVD version of the LMCE install, it will take an entire HDD. So if you only have one, it will wipe it out. If you have 2, well you can figure that bit out
. The way to circumvent this is to use the CD install method. Installing Kubuntu 710 firstly, then LMCE. This will allow you to install it in a partition, vs. taking an entire drive. As to video playback, playing a DVD will work fine for your video watching, however, if you decide to use the LMCE Rip DVD To Hard Drive option, you will need on average of 4 to 8GB of space for each movie. Music works either way using existing songs on a different disk/partiton, as well as ripping your own CD's or downloading Music with your favorite service/sources. LMCE also gives you access to the KDE Kubuntu desktop. This you can use for all other applications like open office, K3B burner, and a host of other software pre-installed. You can also add new apps to KDE via the standard Ubuntu/Kubuntu repositories. Regarding the tuner issue, I know there are a variety of supported USB Standard and HD Tuner cards. These can be found here, in the wiki http://wiki.linuxmce.org/index.php/Category:TV_Cards
Those are the currently supported plug an pray devices
A laptop with dual core CPU's and the amount of RAM you have, can also function as your home CORE. It might be a laptop, but it is more powerful than most peoples desktops
There is a host of info in the wiki. Almost all questions can be answered there or in the forums, and if you are having troubles, from the forums or from your favorite IRC client you can reach the brains behind the whole thing at irc.freenode.net #linuxmce.
Have fun, enjoy the power of what you are about to unleash
LMCE is a wonderfully "complete" entertainment solution