Yeah that will get a good bike. I would try to find I dealer who sells Giant bikes. They have a wide range of mountain bikes if that is what you are looking at.
Note: I do alot of road biking on my so called mountain bike. I actually like it because a) I can hop over curbs and take short-cuts without worrying about bend my rims b)the fat tires take alot of bang out of pot holes. So don't get worried about the road bike mountain bike thing. It doesn't really make a difference until you get hardcore.
Here's a couple bikes I thought a would work well for a beginner.
DiamondBack Crest View: 330$, this is a city bike, not really a mountain bike or a road bike, made mostly for comfort.
Schwinn Sierra 700: 300$, this bike is also a city bike, and has an adjustable stem(holds the handle bars)so it is easier for you to adjust the position of the handle bars to get a more comfortable fit.
Specialized Hardrock FS: 329$, this is more of a mountain bike, comes with shimano Alivio, and SRAM shifters and a Rock Shox Jett fork. This is a good bike if you are wanting to go on some dirt trails at a park or something.
Also, competition will bring prices down a good bit, so the bikes may be cheaper than the MSRP
Happy shopping!!!