Is it acceptable to frame and drywall just one exterior wall in a basement?
I would suggest that you plan out the entire basement before you frame the one wall. Figure out what you would like the entire space to become (eventually) and make sure that the one wall that you are framing will fit in with those plans, or at least is flexible with future plans. It's not fun down the road having to rip down sections of a new wall to accommodate new plans, ESPECIALLY if you were the one to frame the first wall.

While you are at it, make sure to run all the cables and future proofing items that you would want in the future in this one wall, or provide an easy way to have them installed. Install conduit (if possible) for power and another for telecommunications (Cat5e/Cat6, Telephone, etc). If you don't want to run conduit, at least pre-drill the holes, and leave a pull string in the holes to help with fishing wires. I wish I thought of this before finishing portions of our basement.