As ever young Marc is spot on with his advice. Specificially
On the storyboard select the clip you want to split.
Move the Jog bar to the point where you want to split.
From the Clip menu select Split Video. You will now have two video clips on the timeline rather than one
On the timeline, or storyboard, select the second of these two clips.
From the Clip menu select Save as Still Image. This will place a still Image of the first frame of your second clip in the Production Library. Quite conveniently the Production Library view will have changeed to show your still image at the bottom of the Image Library.
Now drag that Image to between your two Video Clips.
Hey presto you have a still frame (or pause) as required. You can adjust the duration of this still image in the Timelien view.
COMPAQ something or other with 500Gb Boot Disk, 1Tb external Firewire Disk, 4Gb Memory and a super duper sound card, 19" TFT Monitor etc etc etc
Sony TRV33e : Sony TRV310e : Canon XM2
Sony Vegas Studio editions to v11
Remember, there is always more to learn than there is to teach.