Dear Pat
So the first thing I did was throw you out

Yeah.
No really I needed to have your user for a while.
Two things. Set your user to default & save before uploading new things. When you did that, clear your browser's cache because it has a tendency to simply use old information it had gathered instead of new, so new pictures mostly will not be displayed correctly. This has NOTHING to do with this forum, it's the behaviour of your local browser. With FF the emptying goes control+shift+r. It empties the cache and reload the page. I made a squared avatar like described and uploaded it, see now its as big as it can possibly can get. Try to avoid rectangle avatars!
Regarding your signature stuff, yes we do have a height limit now. And your linked-in pic exceeds it, in fact it has 222*319. Simple as that, noting you can do about that. 700px width max and 200px it is, yours is 319 px long. You'd have to resize it (you're linking directly from photobucket, so you need to change it there and update your link here), so that the max you'll get 700*200. Else it will be resized automatically here.
For future avatar and signature changes, please
check the Help tab of this forum
(sizes and all are explained there).
I will send you your "new" password that you will kindly renew to your needs.
Cheers!
webmistress