I rewrote the code from scratch (now it's clearly-structured valid XHTML 1.0 Transitional), and it seems that CSS works ok, but I'm still unsure about it's cross-browser compatibility (IE6SP1 and Firefox1.0.1 renders it fine, don't know about others).
Here's what I did: XHTML Page + CSS, <add>but, there's still problems with #menu and #info >_<. Also, I have an alternative version where those two divs are relatively-positioned floating boxes, but there's also problem with their height (I thought v2 was OK, but it isn't). Any ideas?</add>
Of course, I'd like to hear any suggestions about the code I've written (especially about accessibility - I'm new to it and want to learn more about it!).
P.S. And sorry for possibly worse English :( Hope it's still readable.