Classic & Vintage - peugeot concorde new BB help!

Hi, I bought a peugeot concorde bike off ebay a while back, and have been slowly upgrading everything with a view to make it a single speed. Many problems have ensued (namely with the wheels, and the seemingly unremovable freewheel at the back), but the probelm I am having now is with the bottom bracket.
The cranks are held in with cotter pins that just won't come out, so I have accepted that I might have to saw off the whole thing and replace it. I have some campagnolo veloce cranks, but am not sure if there is a bottom bracket compatible with this combination. I'm not a bike genius, but understand there are different threads for BBs, and that french ones seem to be a little awkward.
The bike shops I've been to don't really have any suggestions other than cutting them off and seeing. I just don't want to cut them off and find they can't be replaced, or buy one that I think will fit but won't.
I have attached some images, if there are other I could take that would be more helpful then let me know.
Either way, I want a new bottom bracket and chainset, so can anyone help me identify what kind of one I need for this bike, if it is replaceable? Any help would be much appreciated,
H

1. Hit hard with hammer....end of cotter pin may bend or break
2. Hit hard with center punch and hammer if end of cotter pin bends or breaks
3. Heat up propane torch if 1 or 2 dont work and repeat steps 1 or 2 as needed
4. BB may be Swiss threaded. If so you may be able to swap in a square taper spindle and reusue the old cups.
5. A conventional BSA square taper BB might thread in.....
6. Find a new bike shop
7. 'Freewheel' is held on by a serrated lock ring. Gently loosen with big Channel lock pliers.
8. Rear hub is not compatible with fixie/ss style gearing
9. Find a new bike shop.

Thanks miamijim;
I have been to a few bike shops now, and none of them seem to have people that know about older bikes. They kind of suggest that it's going to be very hard to find the answer, but say that I should look for some really old bike shops, of which there are none near me! However, I will keep looking.
As for the wheels, I will be getting completely new rims/hubs etc for them at some point in the near future, as they are completely out of true anyway and require too much work I think.

Back to the BB and cranks though, I've tried steps 1-3 with no luck. I've also tried drilling them out but there is no give at all. I dont mind cutting them off, but like I said I wouldn't want to do it without knowing it could be replaced.
Is there an easy way to tell if it is a swiss/french/english thread once I have cut them off? Also, is there a link/image to the kind of BB you are refferring to? I'm just not sure if the veloce set I have to replace it requires a specific square taper, or if there is a sealed unit I can buy.

Thanks for you help!

Its either Swiss or English/BSA. If you cut the spindles off the cups will be salvagable which allows for possible use of a square taper spindle thats compatible which the Campy crank. Keep in mind that the new spindle may be compatible based on cup thickness etc....

In many instances English BB's can installed into Swiss frames. Swiss BB ID can be found here:
http://cyclespeugeot.com/Threading.html

i recently started a thread on Swiss BB replacment...a quick search should locate it.