Did you do a nice, slow, 20+ minute warmup prior to this test? It looks to me like your baseline lactate levels, once you started moving, stabilized around 1mmol/L. So you should be OK using 2.0mmol/L as a decent way to find your aerobic threshold. My takeaways from these numbers:
- Aerobic threshold ~140bpm
- Anaerobic threshold ~165bpm
- % difference ~18% (AnT / AeT)
So, you probably have a good deal of improvement you can make by focusing on training below aerobic threshold. No downside to being conservative, and training at 120-130bpm, but you should also be fine spending time in the 130-140bpm range too.