The size of your troop makes a big difference as to which Boy Scouts fundraiser will work best for you. Small troops will do well with fund raisers that have low minimums and/or high profits (scratch cards are a good example); larger troops may do better with a set of products that have a higher minimum. Be sure to check with your fundraising consultant about all the requirements for each fund raiser you're considering, as minimum orders and shipping charges can vary from fund raiser to fund raiser.
Choose something that works well for the people you'll be selling to. It may sound fun to have a Boy Scouts fundraiser where the kids go out and sell candy, but if the people they'll be selling to are mostly parents and grandparents, things may not turn out as well as you'd hoped. Things like tea and coffee work well for adults; save the candy for when you have a Boy Scouts fund raiser where the customers are likely to be in the younger generation.
Basically the main idea is to educate yourself about who your customers are, and be realistic about what sort of Boy Scouts fund raiser would suit your troop. There is no one right answer - as long as you stay informed (ask your fund raising consultant if you have any questions) and take these basic things into consideration, you'll have a Boy Scouts fund raiser that will actually make you excited about organizing the next one.