When it's recommended that people get eight hours of sleep, is that supposed to be uninterrupted sleep? i wake two or three times a night. thx.

Yes: It is desirable that no matter the length of sleep it should be uninterrupted. At your age, it's very normal to wake 2-3 times . Try to not have liquids 3 hours before going to bed.

No: Most people don't sleep a full eight hours without interruption, especially after age 50. Waking to urinate is very common, especially in men due to prostate enlargement; but it is also common in women. Some awakenings are caused by pain, if this is the case, a dose of Acetaminophen at bedtime may make this less likely. If you fall asleep quickly after you wake, no problem.