how can I put my book shelf on hold but not my wish list???? 

Bertie,

Put your bookshelf on hold and make sure your WL books are on auto-request and that you have enough credits to cover them.

You don't need credits to cover your whole WL.  Just keep an eye on ones you are near the top for so can judge your credit situation. (Unless of course you have a big stash of credits).  I usually have a stash of 15-20 credits.  I'll put my shelf on hold and autorequest my whole WL. Then once that dwindles down to like 5-10 credits, I'll come off hold and post WL books if I'm not getting shelf orders.  I do this for postage budgeting and because letting my credits dwindle down inspires me to read some of these WL books I have collecting dust in Mt TBR.

Only use vacation hold on your bookshelf!  Don't use individual book hold!  That puts you at the back of FIFO.  (Unlike the WL, where hold moves you up the line.)