Which video encoding software is best?

I've recently started a new job, and I've been handed the task of converting movie trailers (in a variety of formats) to flv files that are streamed on our website.

Currently using On 2 Flix Pro, but this software doesn't handle all the encoding particuarly well... in a lot of cases it can't complete the conversions, this doesn't seem to be contingent on the file formats.

Can anyone suggest an alternative software title?

Any help would be greatly appreciated.

Cheers.

 

Thanks for the heads up, cost is not really a barrier, just looking for something that will work.

Got a whole folder full of files the On 2 Flix just can't convert to flv.

I'm prepared to try more than one, does anyone else have a suggestion?