The point of that box is to remind you that you need to register mIRC. If you don't like it, then register mIRC as you said you would when you agreed to install mIRC. mIRC is, and almost always has been, a shareware program. You try it for 30 days, then you buy it - as it's not crippleware and still works, the only alternative is to put up with it
I don't know what you mean by "better buttons" - the buttons seem fine to me and it's completely subjective as to what are good and bad buttons. If they were changed hundreds of people would want the original set back (me for one!). Right click the toolbar and you can choose a different set of buttons - either design your own or download another set at sites such as
mircscripts.org.
The right click recent servers menu is a nice idea - there is already a 'Recent servers' menu but it doesn't seem to display recent servers but rather the start of the servers.ini file.
Regards,