Have you read the book "The out of sync child?"
I HIGHLY recommend it. Your daughter might have some sensory issues.
-Angi
It makes sense to try to take your child’s preference for clothes (e.g., color, style fit) into consideration to a certain extent. I do recommend allowing your child some input into the clothes you purchase. In addition, you may provide choices each morning before dressing. But, I strongly recommend that you limit options (e.g., between two shirts) and limit decision time (e.g., 1 min to choose, or mommy decides). Given the long duration of this problem, it seems unlikely that the fit of the clothes is really the problem. If it takes 1 ½ hours to complete the dressing routine, it is likely that the problem is persisting because of the attention that she receives during the process of dressing or because procrastinating allows her to delay whatever event comes after dressing (perhaps a transition to school).
If your daughter is capable of dressing herself, I recommend placing her clothes neatly on her bed so that she can easily find each piece. Be sure to open any difficult fasteners (e.g., buttons, zippers) to make it easier for her to dress herself independently. Set a timer to allow a reasonable amount (e.g., 5 min) of time for dressing. I recommend that you arrange some type of reward if she is dressed within the allotted time period. In some family routines, there are naturally occurring rewards for cooperation. For example, a child might have time to watch a few minutes of a favorite television program or eat a special breakfast if she is dressed quickly. Take advantage of these naturally occurring rewards if you can. Otherwise, pick something that she requests frequently and/or seems to enjoy (e.g., a favorite toy, a small snack), but to which she has limited access. If she does not dress herself in the allotted time period, simply help her to complete dressing. Use the minimal amount of assistance necessary for your daughter to be fully dressed. Do not engage in conversation about her clothes or her failure to dress herself. When she is dressed, simply move on to the next event in the routine, but avoid allowing access to any favorite activities immediately after dressing.
If your daughter is not independent with dressing, a slightly different approach will be needed. With each step in dressing (e.g., putting on a sock), give your child a brief period of time (e.g., 3-5 seconds) to complete the step independently, then provide the type of assistance your child needs to complete the step (e.g., stretch the sock open so that she can slip her foot in, guide her arm gently into her sleeve). Again, do not engage in conversation about her clothes or comment about any uncooperative behavior that she displays. Follow through with dressing until it is complete. Make positive statements when she is cooperating. With this approach dressing should be completed in approximately 5 min.