Susan, the one you picke out looks fine. APC or Tripp-Lite are fine brands for UPS. Spec-wise, you may also want to know how long they can put out their rated VA rating... that's how long you have to either sail throught he power outage, and/or to gracefully shut down your machine.
Along the same OT, I also highly recommend the Tripp-Lite ISO-BAR power strips. They have very good line filtering, with separate filters on each pair of outlets (so they're actually filtered from each other, right in the same power strip).
Speaking of noise, you will want to keep any sensitive audio lines (and especially any equipment that uses audio transformers) away from one of these puppies... UPS's put out a lot of EMI.