OK Willow,
Let's start with some screen shots then... a picture paints a thousand words as they say...
I'm confused about your statement "and when i go to select the background turns black (btw, what does that mean when the screen turns black??)"
Do you mean the whole screen turns black? I've never seen that before. Are you in Track View? Lets see a screen dump of that so we know what we are talking about here. Do you know how to do screen dumps and post them on this forum? If not, we'll go through that first.
In the meantime, I'll post some screenshots of the process that I go through. My screenshots may look slightly different to yours because I'm on Sonar 5 SE but the principles should be the same.
This first one shows the Global Options dialog box with the Editing tab visible so you can see the setting that I use. Not everyone does this but it works for me:-
http://www.synkrotron.com/images/sonar/1.jpg
This next one is a shot of a test song in Track View and you can see that I have 5 audio tracks visible, each with some audio data (clips). Also note that the Now Time marker, which is a straight vertical line, is at measure (or bar) 3. It's important to understand that, at this time, you need to set grid snap on and perhaps set the snap value to at least Whole Note or even Measure so that you know for certain that the Now Time marker is bang on the start of the bar. Alternatively (I hardly ever use this) you can type in the Now position box and set the marker location that way. You can also see along the top of the tracks the song markers called Intro, Verse, Prechorus and Chorus.
http://www.synkrotron.com/images/sonar/2.jpg
The next shot shows that I have selected all of the audio clips. I could just as easily have just selected one clip, and just that clip would have turned black, but the purpose of this exercise (that I originally did for another chap asking the same question) is to lengthen the Prechorus section by 1 bar. The way that I select clips in this situation is hold down my control key at the same time as I am selecting the clips, so each time I click on a clip it is added to the selection set.
http://www.synkrotron.com/images/sonar/3.jpg
This next shot shows that I have split all five clips and you do this by simply pressing the "s" key on your computer keyboard. Because the Now Time marker was at bar 3 when I pressed "s", it split all of the clips at that position.
http://www.synkrotron.com/images/sonar/4.jpg
The next shot shows that I have now selected all of the Audio clips to the right of the split. I have also positioned the Now Time marker at bar 4. I am now about to split the selected clips at bar 4 using the above procedure.
http://www.synkrotron.com/images/sonar/5.jpg
The next shot shows the clips now split. Please note that each time you split a clip the part to the left of the split always stays highlighted.
http://www.synkrotron.com/images/sonar/6.jpg
The next shot shows that I have now selected all the clips to the right of bar 4. This is so that I can move them over by one bar and therefore leave a gap of one bar between bar 4 and bar 5. The move is done simply by clicking and holding the left mouse button on any of the highlighted clips and dragging everything to the right. It's really important that you have snap set to on.
http://www.synkrotron.com/images/sonar/7.jpg
This next shot shows the gap that has been created after the move.
http://www.synkrotron.com/images/sonar/8.jpg
This next shot shows that I have now selected all of the one bar long clips between bar 3 and bar 4.
http://www.synkrotron.com/images/sonar/9.jpg
The next shot shows that I have copied the previously selected clips into the adjacent empty bar. The way I do this is hold down my shift key and then click on one of the clips... keep that left mouse button held down or else you'll end up deselecting the clips that your mouse is not touching. Now carefull move those clips... still holding that shift key down... one bar to the right and hey presto!
http://www.synkrotron.com/images/sonar/10.jpg
This last shot (phew) shows that I have dragged the song marker labled Chorus to the right by one bar, to bar 5, which is now the new start position of the chorus. The prechorus section has been extended by one bar.
http://www.synkrotron.com/images/sonar/11.jpg
I hope that most of that makes sense. I'm at work at the moment and I was going from my (failing) memory. If I get chance I'll recheck what I typed when I get home and post amendments if needed. Or no doubt others will drop by and put me right in the usual fasion
good luck
andy