How can I avoid the startup warnings about deducing proper fonts?
This is highly dependent on your installation, but try with the following font as your base font for SXEmacs and see what it does:
More precisely, do the following in your resource file:
Emacs.default.attributeFont: \ -adobe-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1
If you just don’t want to see the ‘*Warnings*’ buffer at startup time, you can set this:
(setq display-warning-minimum-level 'error)
The buffer still exists; it just isn’t in your face.