i have a couple of flv videos and some mpg videos. they are all low quality and there are less pixels. what can i do to increase the quality of the video? are there any FREE softwares?

In a word; Nothing. You can't add 'quality'.

There are some free programs to convert flv to avi or mpeg but you cannot increase the quality as stated above.
I have tried ANY VIDEO CONVERTER and it works well, and is free. It also downloads the youtube video and converts it for you. Here is a video on how to convert youtube videos and the video is on youtube..LOL

No way of increasing quality. You stuck with what you have.
As for converting videos from one format to another?
You can use the VLC media player to do it.
It's free and lightweight. Makes a great alternative to other media players.

A tutorial for all OS's on how to use VLC to convert videos and even extracting audio from videos can be found on my blog.

You can`t increase the quality, all convert is keep the quality or lose the quality.