Well, the system shows 'em at the same size whatever the size of the pic uploaded. Filesize-wise, try and keep 'em as small as possible (under 10k if poss).
I suggest you to -NOT- write that kind of information on any kind of viewable website, restricted or not, as someone might find it in a search engine or other things that cache webpages (such as www.archive.org or www.google.com). It is generally not a good idea. I am under the impression that you wrote this on some kind of system with many files. If this left frame you are talking about is a separate file, chances are actually very high that someone will find your account info.