TiVo with a CableCARD is the easiest to set up and use and it provides a greatly superior experience to Comcast's crappy DVRs. Whether or not it will save you money is entirely debatable. I don't particularly recommend going the Windows Media Center route unless you are very tech savvy and don't mind fiddling. I did that for two years and found it to be a pain in the ass due to my less tech savvy wife and kids.
I don't care about apathy
Main System: Sony XBR75X940C * Marantz SR6010 * Marantz MM-9000 * MSI Cubi HTPC (OpenPHT/Aeon Nox) * Roku Ultra * Samsung Blu-Ray * Paradigm Studio/40 v.2 * Paradigm Studio/CC v.2 * Paradigm ADP-370 * SVS PB12-Plus/2 * Harmony Ultimate One * HDFury Linker (Zone 2)