I've been calling Continental to get Business Class seats LA to Paris and Barcelona back to LA. for early September. Each time they tell me that seats have not yet been released. Then they offer a route with four stops via Siberia and want 250K miles for it.
Maybe I'm not inquiring properly. What gives?

I called Continental again and got the following
LAX-Newark-Paris-Bordeaux -- and return Barcelona-Newark-LAX. The coach fare is $1130. It costs $450 (+40 K miles) to upgrade to BC/FC. At present the ONLY segment that was upgraded was Newark to Paris. I'm waited listed in BC for all other segments.

I don't know how to evaluate my chances of getting the other long segments to upgrade to business. The trip is Sept 10-27. I'm told that I have only 24 hours to cancel. I know my husband won't fly coach and we are able to buy BC seats.

CO is notorious for not holding release of BF reward seats. There are no guarantees, but I have been upgraded about 95% of the time when waitlisted like this.
If you absolutely must have BF you can purchase. Looking online at www.continental.com BF for LAX-CDG and BCN-LAX is $4656 RT. Lowest coach is $1022 in G class, which can be upgraded for 20K mile +$450 each way (total 1922 +40K miles per RT ticket) but as you have learned you would be waitlisted.

LAX-EWR is a tough route to get FC seats. While you're ahead of all the complimentary upgrades, that is still no guarantee you'll clear the waitlist, and it's a long flight.

Are you only looking at mileage upgrades or can you claim business seats outright? If the latter, see if you can claim Air France's non-stop LAX-CDG. Or see if you can get on DL or Northwest with all seats confirmed in the front cabins.

Continental is having a business/first class sale on flights to Europe, but travel must be completed by September 4. I put in some arbitrary dates in August and drew a price of just under $2900, which is not a bad deal, but seats in this sale are limited.

So if you can move up your trip to before September 4, you might want to consider that. But do it quickly.

My experience with being wait listed for an upgrade is not good, so I am unwilling to risk it. Also, since we fly from CLE, there is invariably a domestic leg on leaving and coming back, and we have never been upgraded on those legs, which isn't a problem to me, since those flights are short.