If you intend to use the core as just a core and not for viewing media, then no, certainly not, choose UI1 and you can get a very basic graphics chip - you can even run it headless if you want, but I wouldn't necessarily recommend that. Most people use their core's in hybrid mode, so you can view media on it as well. But if not, the machine does not need to be high end at all, most of the load will be SQL database queries.
Even the Media Director function doesn't really need very high end video cards. nVidia is invariably the preference, and most people can get away with 6200-7300 chipsets. Although with the coming accelerated video decoding functionality you may want to get a 8xxx or 9xxxx series device in preparation, 8300/8400/8500 are quiet common. All will require you to install the latest nVidia drivers, detailed on the wiki under Display Drivers.
You should be familiar with the necessary network setup detailed on the wiki search for Network Setup, as this is a very important aspect. And generally compatible hardware is important to a smooth setup, I have posted many threads about using chipsets to determine an appropriate motherboard rather than the motherboard itself, so it would be worth looking into that as well.
But yes, welcome to LMCE, and yes good riddance to stupid switching between applications, the MCE interface and desktop, and generally fucking around to get some media to play.... simply unnecessary under LMCE, I cannot remember the last time I had to switch into the Desktop on my living room device, it stays in LMCE media mode 100% of the time (every Windows MCE user I have seen sits in desktop mode more often than not!), and I definitely cannot remember the last time I even thought about what codec or container format any of my media is in, it just doesn't occur to me. I press play, and it plays, exactly the same every time