Worth upgrading to 64bit?

[Brance]

I'm running 32bit Linux Lite on a 10-year-old laptop. Not sure why I chose the 32bit installation - it was some time ago and not important for my purposes back then - but I'm now trying to get more performance out of the machine.

I've just upgraded the RAM from 2 to 4GB, and am now wondering whether I should upgrade the OS to the 64bit version, which poses a couple of questions:

• Is a 64bit upgrade likely to make much difference to performance (for example to better exploit the RAM upgrade)?
  
• Is there an easy way of upgrading, rather than starting from scratch? (as a relative Linux novice I'd rather take an easy option)
  

My processor is a Mobile AMD Sempron 3200+, which lscpu confirms is 64-bit capable.

Any thoughts / advice?