I personally think, updating software is good, and pretty easy. If you have little knowledge of how to use computer and internet then you can do it yourself and not take it to any service center to do it.

I updated my old N73 twice in 10 months, and updated once N76 so far, and never anything went wrong.

While updating make sure:
* You donot stop the process in middle.
* You donot unplug your phone from PC.
* You donot do anything with your phone. No calls, nothing.

Always save your data on memory card. So that if you format and upgrade the SW nothing gets lost. Or simply, make a backup of your data before starting the upgrade process.

If possible please try to write proper title. Proper title can help ppl in searching, and can get more users to the thread to help you out.