In this study we present a client-based architecture that supports time-shift Digital-TV (DTV) features (i.e., pause, replay and fast-forward) and interactive applications. We call this architecture piDTV for Personalizable Interactive Digital-TV architecture. Our study focuses on devising effective techniques for managing the client's data (e.g., textual, binary, and video/audio data) under the local resource constraints. We outline the challenges that piDTV faces and sketch data and resource management policies that maximize the client's QoS adaptively based on each individual viewer's quality requirement. We present a prototype that have been built and describe an array of applications that piDTV can help realize.