P0420, P0335 & P0725 codes on my 06 Altima.

What is your question?

Six months ago the service engine light came on my Altima. The code read was P0420, catalyst system efficiency below threshold (bank 1) which could be the cat converter or the o2 sensor not functioning properly. I put off the repair til I was financially able to resolve it. The lite went out for about 2 weeks but returned again. In January, my car stalled the first time in 8 yrs. while stopping at a lite but quickly restarted. The second time it occurred, took 2x before starting. The last time it occurred while stopping to enter traffic, it stalled with warning & took about 4 tries. I tried to accelerate but could not accelerate past 20 miles an hour & sounded seriously like a human trying to catch his breath for the next 1/2 mile. I kept my gas pedal to the floor for fear of it stalling or being hit in the rear in fast moving traffic til I was able to exit. I shifted it in neutral when I came to the stop light. When I proceeded after the light, it resumed normally. I had the codes checked & they read P0725 & P0335 which is the crankshaft sensor malfunction. I have to find out whether my car is included in the recall concerning this. My question is this: do I still have to repair the P0420 code issue with the O2 / catalytic converter that didn't show up on the latest code reading?