Xian has some nice parks. One of the nicest is Lianhu Park, South of Lianhu Road. Geming Park, South of the Train Station, is another good place to relax. Another good place to go for a stroll is Xingqinggong Park, east of Downtown.
People in Xian are extremely friendly, but most of them do not speak any English. I recommend bringing a Chinese phrase book. It will be very useful when buying goods, going to restaurants, and moving around. Look for a book with phrases in Chinese alphabet and Pinyin (phonetic alphabet).