Well I would trust Jesse's information.

According to the German Wikipedia article the czech / slavic name Růžička is pronounced something like roo-zitsh-ka.

http://de.wikipedia.org/wiki/Růžička

I don’t know if this is accurate (and in case it is, if this was also the way R. R. pronounced it or if he changed it to make it more memorizable / more obvious to pronounce in an English speaking environment).

I once referred to Ruzicka in a presentation using a slightly slavic pronunciation (the best I could manage without being too obvious about it). Afterward, Matthew Carter pulled me aside and quietly informed me that everyone at Linotype just called him Roo-zee-ka.