Well, that might be one option, Talia. Trek聮s 7500 ($660; trekbikes.com) is a bike that聮s definitely built for comfort. It has a very upright stem to keep that common bent-over biking posture to a minimum, a suspension fork and seat post to soak up bumps, and a cushy saddle. All in all, it聮s a nice bike. Similar bikes include the Marin Redwood ($479; marinbikes.com) and the Novara Forza ($550; rei.com).
Giant FCR2 W Bike

You don聮t say why you聮d rather not have a bike that puts much strain on neck and shoulders. Bikes certainly have ergonomic issues, but in a lot of cases these problems go away as your body adjusts to the different stresses and strains. While the bikes above try to eliminate some of those issues, it聮s also true that they create new ones. Sitting very upright concentrates forces into the area of your butt, and that can be uncomfortable. And these are exceedingly pokey bikes; it聮s really difficult to get much speed going when all but standing straight up. That may or may not be an issue, but I mention it just the same.
Don聮t completely overlook bikes that are comfortable but take a more balanced approach to their design. Giant聮s FCR2 W ($700; giant-bicycle.com), for instance, has upright geometry and handlebars so you aren聮t in that road-bike crouch, but it聮s still a speedy bike, with fast wheels and a design that doesn聮t push your coefficient of drag off the charts.
But, if you have some real physical issue that you聮re attempting to work around, then you might want to abandon upright bikes altogether and get a recumbent. A recumbent bike puts you in a fully seated or supine position, with no weight at all on shoulders, neck, and arms. They聮re also quite fast on flat courses because they offer less drag than an upright bike. In the past I have mocked recumbents (all in fun, really!) because of their perceived geek-quotient. But they do solve some real problems with traditional bikes, and those who ride recumbents are uniformly enthusiastic about them.
One problem is cost. Recumbents are not mass-produced, so economies of scale are lacking. But they聮re not too outrageous. A quality recumbent such as the Linear Mach III (linearrecumbent.com)can be had for around $1,500.
Check out 国产吃瓜黑料’s picks for Gear of the Year and 400-plus gear reviews in the 2007 Summer Buyer’s Guide, on newsstands now.