Two main options people seem to use for this are:
PC tuner card, as you mentioned. Based on what software you use (WMC for example) can easily tune TV, and set up recordings, etc.
Other option, is something like the HDhomerun software. This would be a central device, that can then be set up to record things, etc out to a specific PC hard drive, etc, and accessible by other devices... but would then require a playback device on all the other TVs as well.
If the other rooms ONLY have the TV and nothing else.. might be cleanest to just go the tuner route.
GDKitty
Rogers Ignite Xi6, LG 47LV5400 LED TV, Yamaha