I think the interface is pretty effective and finds a good middleground between overly complicated and too simplistic. It’s going to be much easier for people who have never used dosbox before to pickup (far less overwealming than DBTurbo, yet is actually more effective for the most part), but there’s also enough common sense to it that people who already know dosbox can quickly adapt. Yes, there will be some people who think they are above using a cartoony interface, but it’s going to be hard to please everyone.
If it’s something you get a lot of compliants about, it may be worthwhile to consider having the option of toggling between the icons and basic descriptive text lables like EL MB suggested. I wouldn’t change the actual layout and how everything is grouped though. I think it’s really effective how it is.