Firefly was my first contact with the Jossverse. I've heard all sorts of great things about Buffy and Angel, but I hadn't seen either when they were on TV. After Firefly and Serenity I was willing to give them a try. sandy_tyras loaned us the Buffy Season 1 DVDs. Took a while to find time to watch them--Maggie and Jamie get into enough rough-housing without giving them a kick-to-the-head rolemodel--but we've worked our way through them. Now we're hooked.
Last night we watched the last one. Gerry is coming by with Season 2 today.