I'd like to be able to use my function keys without needing the "fn" key itself when I'm bootcamp-booted into Windows. Any ideas?

If your laptop has an Fn key, press it with and without the function key you use to control the screen brightness. Read: How to change Function key behavior in Dell laptops ...

If you need to use your F keys on your laptop for an app or game but it isn't working, there are a few solutions you can use to make life easier.