If you've tried to set up a TV tuner and had problems, or if you've yet to set up Media Center, Watch Live TV in Windows Media Center can help you get started.
When you select a television show or series to record, you'll see various recording options. As shown in the Images section below, these include Record, Record Series, Advanced Record, and Other Showings. Once a program has been configured to record, you'll see a few more options.You should explore these options to make sure that you're recording what you want, when you want. For instance, you may not want to record reruns! These additional options are listed here:
Record Settings offers a new screen that lets you choose between setting settings for the specific instance of the television show that you’ve selected, and editing settings for the entire television series. For example, if you only want to edit the quality setting for the one television show you’ve selected and not the entire series, select Record Settings, and then select Settings for this episode only. If you want to change a recording setting for the entire series, select Record Settings and then select Settings for the entire series. 
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Do Not Record cancels the scheduled recording for the current episode or the entire series, depending on what you selected in Record Settings and when you opened the Program Info section.
Keep until shows the Keep settings for the television or television series. There are several options – Do Not Change, Keep until space needed, Keep until (a specific date), Keep until I watch, and Keep until I delete.