You need a video converter. There are two kinds of them: desktop and online. Online ones are free (the majority of them). So I prefer to use them. I can recommend you Online Video Converter and Online Uniconverter. In any case, you can Google by yourself and choose any you will find convenient.
I use a Flash to Video Encoder PRO. Very easy to use program. You can convert flash files to video movie AVI, mp4, ASF/WMV, mpeg files, etc.
I think the FLV to AVI MPEG WMV 3GP MP4 iPod Converter is your best choice, it always works well for me. it can convert Flash Video FLV to AVI, FLV to MPEG, FLV to WMV, FLV to MP4 format.with excellent quality.
Here is a guide about how to convert FLV to WMV, same way to convert FLV to AAC because Daniusoft video converter support convert FLV to AAC too.
With trp converter software you can convert trp file into avi file. Not this but you can also convert trp into flv, mp4, asf, wmv, m4v, mov, mpg, etc. The software provides graphical user interface.
Windows media player doesn't support flv format,so you can't play the flv files on it. You can use convert flv files to wmv,avi,mp4,etc. I recommend you 4Media FlV to WMV Converter.It is the professional FLV to WMV converter software which can convert FLV videos to Windows media files including WMV, ASF videos and WMA, WAV, MP3 audios for playing on Windows media players and Windows mobile devices.It's easy to use.You can have a try. You can use VLC player
An MHT file is a web page and a WMV file is a video extension. You can convert an MHT file to a WMV file using Xilisoft Video Converter Ultimate.
I just found this thing called flv to wmv video converter (it's for mac, if you need windows get FreeStudio and use 3GP video converter) it's free.
The best way to convert FLV to AVI is to use software program
Nero 10 is a dvd burning freeware, it can convert a flv file to dvd eaily.
Search a normal flv converter or a video converter ultimate It supports convert FLV file to popular video formats including AVI, MPEG, WMV, DivX, Xvid, ASF, 3GP, MP4, iPod, PSP, Zune and convert FLV to audio formats MP3, WMA and WAV.
Throw your .flv files into a converter program like Free HD Video Converter Factory or VLC (if you'd already have it installed), and choose WMV format to make the conversion.
Go to cnet.com and download "free convert MPEG WMV to MP4 FLV AVI converter" you can use it convert videos to play on your iPhone, Xbox, PSP, and iPod.