A quick way to get the firmware of your Nokia Nseries handset is actually from your desktop.
If you use Nokia PC Suite all you need to do is right-click the mobile icon in Microsoft Windows Explorer under My Computer to give you a properties box like below (click to enlarge):
I have both Nokia PC Suite and Nseries PC Suite installed on my machine and for some reason they appear to give different details (I’m not sure which is which though).
One has The Phone Model, IMEI Number, Phone Software Version and Phone Software Date. The other has just the Model, Firmware Version & IMEI Number.
Handy to know.