I can understand your frustration and feelings that you believe your daughter may be losing out. Just one or two badly behaved or disruptive children can make a big difference to the learning in any classroom. A productive and secure ethos and a calm, reflective atmosphere are vital to set the stage for quality education.
The situation you describe is the beginning of your daughter learning some lessons for life. The reality is that she will continue to come across a broad range of people in school, during social activities and in future workplaces, some of whom have challenging or difficult personalities.
Teachers tend to spend a lot of time and effort trying to get a good balance within each class
In any class there is a range of both ability and behaviour - in some cases this range can be wide, and this can be challenging even for experienced teachers, especially when they are dealing with classes of 30 or more.
One of the most useful things you can do at this stage is to help your daughter build resilience and provide her with strategies to cope.
At school, she needs to be encouraged to focus on the task in hand, avoiding distractions and not being afraid to ask the teacher or her peers for help if she is stuck. Discuss with her how she can reduce her distractions. If she comes up with some of her own ideas, it will help her to put them into practice and make good choices about her own reactions and behaviour. Self-monitoring is a powerful tool.
Talk to her about what type of learner she is and how she learns best. Perhaps she has options to choose a compatible seating partner, find a more isolated spot to work or wear earphones to aid concentration. If the teacher is aware of how your daughter is feeling, he or she can check in with her to make sure she is comfortable and confident in her learning.