I suggest you check out
www.HaroBikes.com, I work at a shop that is a dealer for Haro. They have a "comfort" bike that sounds like it would suit your needs very well. It's called a "Del Sol". The 2.0 model is steel frame, alum wheels, grip shift, adjustable stem and suspension seatpost. This retails for $259.00. If you want an aluminum frame and a front suspension fork go for the 3.0 model for $319.00. Their entry level mountain bike is under $300 and is well made and decent components.
L8R G8R
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"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
"Your Bike Sucks" - Sky Yaeger