It really depends on where you live and what kind of roses you like. Roses need sunshine, heat, fertilizer, water, and bug protection. Some areas of the country are not as well suited to roses, but if you are willing to amend the soil, invest in a quality plant (Jackson & Perkins roses are excellent), and water and fertilize regularly you should be successful at growing roses. Keep in mind that it takes several years for the plant to become established, so don't expect too much right away. If you really want to grow the best roses, your best bet is to join your local rose society, most groups meet in the evening once a month and will have featured speakers and rosarians to answer your questions. I hope this wasn't too much information!
P.S. I would always put cut up banana peel and coffee grounds around my rose roots in addition to rose fertilizer, they always gave me lots of blooms!