A quick question about my new 40D

I bought my wife this camera so, I could use her as a backup shooter for weddings. She has a problem with the lcd turning off every time she review a picture. Is it a way to stop it from doing this? I know on my 5d when you hit info it comes back to the information screen and stays like that forever, but on her 40D it goes black after you review a picture. If it is possible to fix please let me know. Thanks in advance

Go to Menu, first red tab, scroll down to Review time.
There you can select between Off, 2, 4, 8 sec and Hold which will keep picture review forever.
Press SET to confirm your selection.

However, I don't recommend the last one.
LCD is big power consumer, permanent picture review will quickly drain the battery.

I think you mean that the INFO screen disappears after manually pressing the review picture button. The 40D does so, and the reason is of course that the INFO screen is in most case redundant. The camera's settings are shown on the top display all the time.
If you still want to look at the back, you can set the camera to go to that screen after pressing INFO only once, but that's the only thing you can do.

Thanks again. I was planning on setting it to 4, so she can have to review her pictures

Your camera has a review button that will allow you to look at and review your photos for as long as you'd like. Any reason your wife is not using that? But as pointed out above you can change the time your camera reviews a photo after a shot, but it still may go away too quickly or get annoying having it stay up too long.