I'll join to help the Dollhouse lovers. Obviously you can see that Buffy and Angel are both totally worth it.
Dollhouse is a harder sell. It's a slow burn for sure. The first couple of episodes make it seem like a kinda offbeat procedural but then you start to realise that the larger narrative of the show is moving along. Then eventually the "Case of the week" is suddenly thrown out the window and the large story unfolds.
Buffy and Angel is awesome but hella long. If you're looking to watch a smaller contained story with a beginning, middle and end, watch Dollhouse.