In many cases there is no sense to convert.FLV videos to DVD format, because the quality of the resulting DVD Video is very low. So make sure that your source videos are good enough.

If you wanna watch your FLV videos on a large screen, you may use the video-out of your graphics card (if it has one). I haven't seen any standalone DVD players supporting FLV format, but you may use standalone devices like Apple TV to watch such videos. Some of them even allow you to watch YouTube videos without downloading them.

Digital Media Receivers and supported formats:

• Apple TV supports QT, MPEG-4 ASP/AVS
• NetGear Digital Entertainer supports MPEG1, MPEG2, MPEG4, AVI, WMV, Xvid
• Sandisk TakeTV supports MPEG4, AVI, WMV, Xvid.

It seems like conversion from .FLV files is required for all of them.

Some video converters to try: freeware DVDFlick, MediaCoder or shareware Replay Converter, Cucusoft Ultimate Video Converter.

Related threads:
Converting .FLV videos
How can I burn .WMV files into DVD or VCD
How to burn DVD from .RM video files