Probably so many modules are included in a default compile is that exact reason - maximum compatibility with a wide range of hardware
i.e most computers.
Only way to do it is know what hardware you've got, file system your using/want to use etc.
If you hit shift+? you can get a description of each option - usually
it's blatantly obvious if you've got the hardware on your computer
(apart from scsi and scsi emualtion for cdwriters) or whether you need the functionality of a certain module.
The hard way to do it is to remove options a few at a time, recompile, making sure you've got a copy of your original kernel to boot in to.
Apart from that try and find out as much about your computer you can and follow the advice of the information that's provided when you press shift+?
Like most people I could give you a config file but it's customised specifically for the machine it's on.