So I updated iTunes yesterday, and now I cannot right click on a song and convert the song to aiff, which is what Final Cut likes the best. Is it my computer or is this phenomenon happening to others who updated to the newest iTunes?

Pretty easy...Use the HELP button ...

looks like they moved it to the " Advanced Button " on the tool bar....
but you will need to change the preference setting of " import " to
the desired format... I guess this is Apples way of letting you change
the program for PC or MACs...

Now it is located under the advanced menu on the toolbar.
Why in the world did they take this off as a right click option.
Oh well, I love extra steps.

I use Switch.

It's a free program for Mac, which you can easily drop files into, put them all over into AIFF or MP3 or FLAC or...
Works pretty fast, simple and clear interface, and I don't like the fact that if I would use iTunes it would get into my library etc.

I just drag a file from my iTunes to my desktop, drop it into switch, and convert it to an AIFF on my editing disc of the project. Then I remove the MP3 copy from my desktop. Fast, easy, and clean.

Open the MP3 in QuickTime Player - since you have FCP, you have QuickTime Pro so then use File > Export to make an AIFF file.