I've traveled to WDW several times alone. I've stayed at Pop, POR and Poly. I've never felt unsafe at Disney but I also make sure I take some general precautions.
- Stay aware of your surrounding. Which, honestly, in today's day and age we should all be aware of our surroundings and what's going on.
- At night, I stay on the beaten path - I don't go offsite and I go places that Disney transportation can take me. Now with the Minnie Vans, that actually opens up quite a bit more than it used to.
- If something/someone is making you uncomfortable - ask for help. Theres lots of cast members around who are happy to assist.
I'd be comfortable at the All Stars but if you aren't feeling 100% about it - you book/ask for a preferred room near the main areas. Tends to be plenty of people and lighting all the time.