Originally Posted by silentC
There are only a couple of things I can think of that might cause you a problem:
1. The wall could be load-bearing. In a 1950's house there's good chance it is. In that case, you would have to look at alternative support for the roof. Probably switching it to the new bit of wall would be the way. You would have to dismantle the existing door opening and replace it with a full-height stud wall if that was the case.
2. There may be utilities running through the wall, most likely power but there could be water too, depending on the situation. You'd need to reroute these.
Otherwise, I agree it sounds do-able ;)