Here are the pictures of the shrubs I am talking about.

Here is a link that might be useful: Pictures

If you want to keep them, I would recommend cutting them back slowly to see if the lower parts regrow. They are not growing at the bottom, in most cases because of a lack of sunlight. If you open up the branching habits and let more sunlight in, you may get them to regrow (depending on what they are). I have used that technique with the spirea at the front of my house over the last 6 years we've been in this house and it's worked really well.

If you're in for a few years worth of that kind of a look, then you would be better off starting over, but bear in mind that these are established and will take less water to maintain than new shrubs.

With the amount of knowledge and expertise on hand remedial measures may not turn out well. I would clear the area first take time to have a look at the bare space and have it designed when you know more about what you want.

Take a close-up photo of a branch of each shrub. The photo should give a clear view of some individual leaves and also of the arrangement of the leaves on the branch.

Post the photos on the Name That Plant! forum and ask for identification. You can post each shrub in a different thread (with different titles for each thread) or post some/all the shrubs together -- but if you do that, it's better to number the photos.
http://forums2.gardenweb.com/forums/namegal/

Then either tell us what the shrubs are, or go to the Shrubs forum and tell them what you have and ask about pruning, or Google each shrub by name with the word "prune" or "pruning." You want to know whether each type of shrub can be pruned back to "dead wood" (the brown areas without leaves) or not -- and if they can be, when the best time to prune would be. Some will grow new branches and leaves, but others can't.

The general rule will be that the evergreens (conifers) will not grow back from bare wood, while the deciduous ones probably will. So will any broadleaf evergreens.

The other way of categorizing them is (a) which ones you like and which you don't, or (b) which are good in the place they are and which are not. You might not need to know what they are to answer those questions. A plant you hate that's in your way = get rid of it. That may encompass, as Ink suggests, pretty much all of it.

There is both a pro and a con to keeping such big shrubs. Yes, they may not need to be watered, but that is because they have large root systems that are able to suck all the available water from their surroundings, handicapping the growth of anything new you might plant. Also, those large root systems are capable of pushing out a lot of new growth every season, which = lots of pruning. And again Ink is right: you need to know how to prune to do that with good results.

I'm for yanking them - whatever they are, they are not treasures, and the landscaping has basically reached the end of its planned lifespan. The trees in back, however, are doing a pretty good job of screening for you, and may do for some time yet.

KarinL