I was wondering about caulking baseboards because we have some gaps between the old baseboards and the wall, so we were thinking that putting caulk in there would make it look better. Turns out we were thinking right. Here is a video that does a good job of showing how to apply and “tool” the caulk.
I also wondering about caulking crown molding as well, which seems to be an ok thing to do according to the sites I have viewed. This video gives a couple extra tips, such as filling in nail holes, and using windex when applying caulk.