This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
There rarely is a single "best" of anything; it heavily depends on the circumstances and requirements (of which we know nothing). If JasperReports won't do, I'd probably look into Data Vision and Crystal Reports.