Replacing windows is actually one of the easier DIY home jobs you can do. Hell of a lot easier than building a deck that a lot of people do. They are installed after framing and meant to be removed if they break. Removing the trim inside and outside will give you access to the fasteners holding the frame in.
Usually, the hardest part is finding windows that fit and match your taste.
Usually, the hardest part is finding windows that fit and match your taste.