I'm trying to hook up a surround sound .can I buy a dvd equipped with a receiver?

Yes, lots of home theater sound systems include a DVD player.

Yes, but many of those systems are made to work almost solely with the speakers they come with. The benefit with all-in-one systems (or Home Theater in a box systems), is that they take up less space and are usually easier to connect.

The downside is that they usually come with only a couple of digital connections. They also usually have a lot more distortion in the audio. And if any part of the systems fails, you usually are stuck with expensive repair/replacement costs.

The other kind of systems are when you have a separate A/V receiver, subwoofer, center speaker, and 4-6 satellite speakers. These systems sound the best. If a part fails, you can usually replace a part (essentially they use standard parts). And have plenty of connections. The problem with these systems is that then you also have to buy a separate DVD or Blu-ray player. They take up a lot more space. And they can be a bit more expensive (before buying a DVD or Blu-ray player, they usually range from USD$600 to an near unlimited max).