Next time, put your question into your post, and put a general description of the topic in the thread title.
Moving on.. how exactly is your Fn key "stuck"? Does it not turn on/off your wireless card, or adjust your volume, or adjust your brightness? Or perhaps.. does it do all of those things and you just don't see the display indicating that it worked?
If the second scenario is right, re-install Quickset, which can be obtained on the Dell website. Just enter your laptop ID number and it'll give you the proper drivers and programs.
on this laptop the default behaviour is that you cant access the function keys (F1, F2, ...) unless you press the Fn button.
the normal meaning of the keys is "turn off wifi, switch screen output, volume up/down, etc"...
this is very annoying...
there is a setting in the BIOS for swapping the behaviour. then the keys are functioning as "function keys" again!