I would go to the website below (Crohn's and Colitis Foundation of America) and read about all of the medication options to treat UC. Specifically, read about the Aminosalicylates, as they are the most "mild" class of meds used to treat UC.
If your inflammation is much beyond the rectum at all, the suppositories won't do anything to heal it, as they just don't go up that high. Enemas will reach higher, but are still limited. I would definitely request to try enemas and oral 5ASAs before going on prednisone.
Symptoms began in November 2008, ~4 weeks after giving birth to my son.
Eased for ~3 weeks in December, possibly b/c of probiotic use?
Returned in January 2009 (with a vengeance), diagnosed with pancolitis on January 30.
Currently taking Asacol (400mg 4 pills 3x daily), Rowasa nightly, Culturelle probiotic, and Zoloft (25 mg).