Thats a shame to hear about Lightworks beta not opening your movs - you should report that as a bug if you've not already. I presume they play fine under VLC or whatever you normally use do they? 3gp is such poor quality I'm not surprised Lightworks aren't bothered about supporting that as its unusable for any semi-serious purposes - I wouldn't waste their time asking about it personally.
As for converting your files- there is winff which is free for both Windows and Linux as is Lincoder, which should run on OSX too I'd imagine as its just a Java front end for mencoder.
Sony Vegas may be cheap but KDEnlive is not only totally free, its fully open source too and if you did have some Linux machines then its installed with one simple command under all popular Linux distros hence very easy to install and learn/use.
I'm waiting for Lightworks to get released for Linux before I try that but I expect KDEnlive will be easier to use for beginners and kids (and everyone else too). KDEnlive is more than powerful enough for teaching kids the basics of video editing so I'd recommend anyone who's not locked into Windows for their video editing check it out.
Sorry Danboid but you're wrong it's not a bug they don't support those codecs in the free version at all it's on their website I looked at the product comparison of the paid for vs free versions. As for the 3gp sorry mate but you're dead wrong there too those are from my Samsung Galaxy S2 and they're shot at 720p so hardly crappy and unusable at all. From a codec PoV it might not be the best/most versatile but you're wrong on quality front, very very wrong maybe back in the early days with a Nokia phone but the quality is amazing tbh!
Anyway it's a codec paid for issue not a bug. I'm quite taken with the cloud based jobbie posted earlier works really well, fast and doesn't need much in the way of local resources very nice. I might have a go with Lightworks occassionally if I transcode my files first or I might even pay for a copy as it's so cheap but OOTB experience with the free version not good for my purposes sadly.
As for directly transcoding Format Factory is fantastic, easy to use produces great results and is genuinely free. I'll have a look at what you suggest will see if it's any good but my general experience of AV stuff and Java = bad but with it just being a front end it's probably ok.
Whoah! Chill out on the 3GP thing please! I'm just giving a few free software hints and tips mate! :)
You seem to be right though - I thought there was a res or bitrate restriction on 3gp but a quick scan of its wiki makes no mention of such restrictions.
Nonetheless, 3GP is not a format I would recommend anyone ever intentionally transcode to, mainly due to its limited support on both hardware and in software. xvid/avi is best for compat where quality is not a priority then I'd encode to webm if you want better quality and smaller file sizes but the file only has to play on computers.
webm is my video format of choice because its open source, royalty free, high quality, good compression ratios
You can play webm files under FF and Chrome without any extra plugins, so there! :)
Remember to only use xvid and webm for distributing your final edits - you should avoid lossy formats like these during editing!
At my workplace we use Pinnacle Studio 14 Ultimate, I would reccomend this. Its really easy to use.
Here is their website - http://www.pinnaclesys.com/PublicSite/us/Home/
If you're still struggling for a free solution may i suggest VLC Movie Creator basic but easy to use, or the new windows live essentials Movie Maker, basically the movie maker replacement. I think they have released a new version this week too.