The Bluetooth Card on the 1535 is the same 320 card used on the E6400. If you've already got the Chipset Drivers installed try that one from the Dell site.
For Fn+F2 to work you'll need to have the Dell Quickset Utility installed which interfaces between the system BIOS and Windows. The utility is model independent so download it from the Utilities section of any XP supported Dell laptop.