https://ark.intel.com/products/72055/Intel-Core-i5-3337U-Processor-3M-Cache-up-to-2_70-GHz
TJUNCTION == 105 C
TJunction Temperature is the maximum temperature allowed at the processor die.
This basically means 105 degrees Celsius is the temperature at which point throttling back begins... So the speed / clock will be reduced. If the temperature doesn't start dropping then there are other features in place such as an automatic computer shut-off to prevent permanent damage..
You should also have settings in your BIOS to change the auto shutoff temperature, or other measures - however I'm not sure whether or not the 105C is configurable - I believe it is a set point when automated protections take place to prevent damage...
Now - since you're on a laptop, try to keep the temperatures as low as possible, especially if the laptop designer put the battery close to the processor... Heat will damage a battery if it is close - luckily with most the battery is at the rear or near and the processor is a bit away - although some laptops have battery slots on the button under the processor..
As for day to day options for temperature - go for the lowest possible because the lower the temperature the longer the life. And because you're on a laptop..
If it was on a desktop then you can just leave the computer running 24/7 which would allow for an even longer life because one thing which kills processors is the constant heating and cooling from turning them on / off ( applies to most electronics actually )... My PC has been stable for 10 years overclocked from 2.4GHz to 3.0 on air and its stable because I don't restart, I don't shut down - I keep it running 24/7 so there is no shock of huge temperature differentials or electrical surge...