I'm not sure if I'm misunderstanding your question, but your ubuntu bash (top right window) should have access to your Windows-based disks under /mnt. For example, on my machine /mnt/c/Users/Scott/Desktop is my Windows desktop and I can read/write files there from vi for ex. I don't believe the opposite is true just yet. That is, I don't think you can explore into your bash world from Windows explorer.
What I've been doing as a developer is to host projects on my d: and point the linux-based tools to that /mnt/d/projects/someproject/ folder.
Make sure you update your Windows builds periodically as they seem to be fixing a lot of issues with each build, especially around sym-links and crossing FS boundaries between Linux/Windows.
