Dell Inspiron 1545 - Replacing Thermal Compound

I have a Dell Inspiron 1545 laptop which has been randomly freezing lately, so I need to replace the thermal compound. However, I haven't done this before so im unsure on the exact process.

I have a few questions.

1. What type of thermal paste is best for this laptop? I read a comment on a YouTube video where someone said that Arctic Silver thermal paste isn't the best for this laptop and they recommended ceramic thermal paste. Is that good advice?

2. Are there any good guides which show the process of replacing the thermal compound in this laptop?

3. Does the thermal compound only need to be replaced if the CPU temperature is too high i.e. above a certain level? According to Piriform Speccy, the CPU temperature most of the time is 37°C and sometimes fluctuates higher than that.