keep location/change the rest

My question is:
Can I keep my blog address and get rid of EVERYTHING else? I feel like I need a fresh start, because each time I try to change themes, my blog turns into a bigger mess, and when I read (for HOURS!) about what to do, the discussion is WAY out of my league, involving things that were not required to set up the other simple, successful blogs I have done. I had the blog at hand put together by professionals, and I am trying to make aesthetic changes, but each time I try to change themes, it is a disaster in a many different ways. Can I somehow start over but keep my location?

Any advice? Thanks much!!!!