Depends on machine
iMovie will do what you want to do. It is enough, however, for any extended amount of Video editing and processing, I strongly recommend Final Cut Express.
I have made several little videos using the exact effects that you mention in iMovie but the wait times and quality of the final product is not quite up to par.
Spend a few bucks for a long term investment and get Final Cut Express.
And finally, as my title says, it also depends on the machine you have. If you have a G5 beast, then you could get away with all the editing and processing just fine in iMovie, without wasting too much time. If you have anything less than a G5, you'll be waiting and waiting and waiting for iMovie to do the processing and it may not be what you expect. iMovie gets funny like that.
Before anyone comments on this, keep it in the context of what the end goal is of the video.
Oh, one quick question, what is D.R.??
Take Care,
Quark