compact dslr camera

I really a compact DSLR. I travelled around europe with a big dslr and it drove me insane having to carry it around all day. I only borrowed it for my trip, i have never owned a digital camera but mainly shoot using an old cannon film camera. I have used a fuijifilm and find it very easy and fun, plus it looks great  but it does not have an interchangeable lens system. 

Are there adapters you can buy for this camera and different lenses (that dont necessarily go with the camera but still work) or do you only have one choice? Also fixed vs interchangeable lens cameras? Which do people recommend and why? I am torn between this awesome looking easy to use fujifilm and the sony nex /interchangeable lens camera 

THANKS!