Gardening Methods

Can someone please help me identify these trees in my backyard? (This is in Arizona)?

I bought a house a couple of months ago and I’m wanting to make some changes to the landscaping. I really want some fruit trees in there and also some shade trees. I have 5 of these trees in my backyard and one small one in front and I’ve been thinking of getting rid of them, but I really need to know what they are before I chop them.
I looked on the web and they look somewhat like California Pepper, but the leaves aren’t exactly the same I think and the berries are not red, but whitish. They send u suckers like crazy, and I think they’re kinda messy. They’re probably pretty drought tolerant.
Here are some photos
http://www.cnw.com/~ulicip/Garden/Tree/branch%20closeup.JPG
http://www.cnw.com/~ulicip/Garden/Tree/berries%20closeup.JPG
http://www.cnw.com/~ulicip/Garden/Tree/Tree2.JPG
http://www.cnw.com/~ulicip/Garden/Tree/Tree1.JPG

It does look like a pepper tree ! There is such a thing as a white pepper. I cannot be absolutely sure, but 98%.

Arizona Backyard by Ryder