Hi kxes
and welcome to our forum
This is usually solved by changing the CSS of the template that is used for frontend. In our case, it was enough to add following line at the end of the css file:
#jform_jopensimregister_jopensimavatar label {width:200px}
but depending of the template you use, additional things might be necessary (e.g. something like "float:left;" or similar).
Greetz
FoTo50