Safe mode will turn your graphics settings all the way down and disable a lot of the graphics options. I had to play in safe mode for years while on my old laptop since it would have trouble overheating.
Draggynn on Virtue: lvl 50 Storm/Psi, 1389 badges
Draggynn's Guide to Storm Summoning(Gale-Tornado, updated 6/25/2011)
Avatar by Wassy full reference here
So what is the diffrents in playing in safe mode and not playing in it?