Hi Jan-Ellen,
Swimming and walking are the best exercises you can do, just because it's not a weight bearing on your joints.
When I go swimming, I remove the socks. I can just imagine how uncomfortable wet comp. socks could be...
Also, I don't think hot indoor or cold outdoors really makes a diff.
*BTW, I'm the one that moved the posts to a more suitable forum, you had this in "Cerebral Thrombosis"*