Can I Sell My Game Ideas?
No.
Everyone has ideas, and regardless of their actual merit, everyone thinks their ideas are just as good or better than anyone else's.
This means that even if you are capable of providing truly outstanding ideas, no one is going to pay attention to them.
On top of that, ideas are free. Anyone can come up with ideas all day long. However, implementing those ideas costs millions of dollars and can take years. So if you weigh the "costs nothing to produce idea" vs. the "costs millions of dollars and years of effort to produce software" you will quickly come to the conclusion that publishers who spend those millions of dollars don't care about ideas nearly as much as they care about implementation.
If a group has fairly decent (but not close to outstanding) ideas, and can develop and deliver a solid product, they are worth infinitely more than a group that can create OUTSTANDING ideas, but cannot develop a product.
As a final note: Everyone would rather be working on their own dream than someone else's. If any choice comes down to "we make our own stuff" or "we make someone else's stuff", and the someone else's stuff does not happen to be the latest hit movie or a branded game like Tiny Toons or a fantastic new Spinal Tap: The Game or something, the "we make our own stuff" wins.