In the cases I have seen where spouses file separately, each may claim the allowed exemptions. When spouses file jointly, many of the exemption amounts double.
Hope this perspective helps!
You should get an experienced attorney to review this matter. The attorney will have to understand all your property and review your wife's BK papers in order to determine what exemptions you should use.
Get an attorney.
You can use the California set of exemptions that best suits you as long as you and your wife are friendly enough that she'd be willing to sign the required waiver (only for the duration of your bankruptcy case) for you to be able to use the "wildcard" set of exemptions. Regarding what you could or could not keep, that's depends on things like loans on the cars, other assets, etc. You definitely should consult with a qualified bankruptcy attorney in your area.
This reply does not constitute legal advice or establish an attorney-client relationship.