"How can I as a gentile meeting or inviting a Jewish person into my home show respect? For example, should I wear certain clothes or serve certain foods?"
There are many different types of Jews. More orthodox Jews would appreciate it if you dressed modestly and offered them food that is kosher. More liberal Jews, which are the majority, may not be offended by less modest dress or non-kosher food (although even Jews that do not keep kosher may have an aversion to pork and seafood). However, they may feel offended if you wish them a "Merry Christmas" (rather than "Happy Holiday") in December or try to persuade them to believe in Jesus as the Messiah.
Basically, don't assume a Jewish person is Christian or should become Christian. The best way to show respect is to simply accept that Jews have a different heritage, beliefs and practices.