I not see a compatible PCI-E slot on Intel® Desktop Board D2700MUD Interactive Layout for videoboard. Conventional PCI cards are present on market, but made unofficially from GPU makers via third-party 'bridge' chips and usually are crap. Conventional PCI bus bandwidth also is too low for HD movies.
the new Intel Atom processor have integrated video (GMA3650) that are capable of Full HD (h264 and vc1) with hardware decode, but only in Microsoft Windows (32 bit) due for missing driver for other OS.
I use XBMC video player with DXVA activated and decode full HD video in excellent way (used CPU is only max 10 - 15%). My mb is DN2800MT, but yours should have same video part inside and you should obtain same result.
For HDMI connectivity you can use DVI to HDMI adapter that don't have big costs.