1. you can usually find straps, clamps or hangers and loosen the screws to get some movement
2. if you cannot use a mini pipe cutter, you can always use a hack saw to cut the pipe (just make sure to cut as straight as possible). I would *not* use a circular saw.
3. you need to get some space between the pipe and studs to insert some type of heat shield (sheetmetal as allan said, or oatey flame protector at min - http://www.homedepot.com/buy/oatey-9...l#.UGOBu6O2GE4
). if you have a shallow baking pan, that works well because you can add some wet cloth to the wood side, cover it with the pan for protection.
regardless of how you do it, you need to have a fire extinguisher handy (and know how to use it in advance).
4. if the movement is fixed so that after cutting, you cannot spread the pipe left-to-right, you will need to use a sweat or repair slip coupling (http://www.familyhandyman.com/DIY-Pr...-pipe/View-All
i don't think sweating a pipe is that difficult; it just takes a lot of practice (and patience).
if the work area will remain exposed, you may want to consider push fittings like SharkBite, though I would recommend sweating the pipe.
Post some pictures of the area and I am sure pros here can help you out.