I guess most english books convert fine in Calibre,and for russian ones i need open html file in Firefox,and check,what encodings they use.Btw..found my taskbar clock too.Seems i turned it on for only in reading mode.By look of it,MS Office Word is quite good for recognizing txt,rtf,doc encodings.
Sidenote...found some unused fast 4 gigs sd card

.My camcorder card it was sold with (aka too small for full hd camcorder per se,replaced instore asap).Formatted it and inserted.DO PRS-650 fit simultaneously both SD and MStick slot cards?I dont have MS card home to try out.