Have you downloaded the 46 meg patch that Pinnacle have released for Studio 9 have released?
That solves some issues, but the programme in my experience becomes very slow and overprone to crash once that stu file gets to a size.
Save - Ctrl S every time you complete an operation, because that dreaded message "Studio has encountered a problem and needs ot close is all too frequent."
Also I gather that having Roxio drivers (was adaptec) for programs like drag to disc loaded in background are unhelpful. Nero is apparently much better and less prone to interfere with other drivers. Dell recommend it too.
I have to admit, I had Studio 8 and only bought 9 because I had a couple of projects running which I didn't want to restart. In the end Studio 9 went back to the shop because one just could not keep it stable, (even after the new patch)and the final straw came when I went to burn a DVD, the programme did all the rendering, but hten locked up. Ctrl Alt Delete, and the stu file was corrupted. that was IT.
I now have Magix Edit pro 2005, which is cheaper, far more comprehensive, a lot more flexible, and while prone to crash if you don't have the latest chipset and video drivers (I do now and its very stable) at least if it crashes you can save the project before it dies. Although the editing side may lock, the file handling side doesn't - so you just shut it down, flick up any other programm to clear the memory, and relaunch. Lost time - about 20 secs.