It will be a fresh install. If you decide to go back it, you have to wipe out
the newest kernel and replace it with the edgy one. This is very difficult for a
even the novice user. Because it does not all ways work. Because some of the
software like firefox is tied into the kernel and you end up with one broken
system and have to reinstall from the get go. Thus it is not advisable to do so.
Why do you want to go back to Edgy?

I had been trying to install cinelerra into 7.04 with no success but I
had used it in edgy, where it worked quit well and was easy to install.
At the moment I am think in terms of reformating the drive with windows
installing it and then put edgy on to install cinelerra on. It's a lot
of work, but with a little luck I can maybe doing video by tomarrow
night. That way I will have windows as a back up for while if I can't
figure out how to do something. I had thought I could just back up with
synaptic to edgy but if that's not doable then this may be a better
solution for me. I am about out of time so I need to get something
going. I may have to buy Premeimere to get working.

You have likely considered this, but in case you have not - is there
anything in Ubuntu Studio that will do what you need?

No whats in fiesty isn't the problem.. The problem is Cinelerra is not
in ubuntu studio and I have spent a lot of time trying to get it set up
and i am running out of time I need to get this project done. I have
been struggling with this a couple months, learning ubuntu and
cinelerra. I would like to use it but I have to do something I know
will work. I just priced Premeire pro @ over $700.00 and that does't
include the price of upgrades every couple of years. Even worse than
that a few crashes and XP is corrupted and has to be taken back a couple
of days to get it working again and sometimes reinstalled.. I'm not
happy but I have to do something pretty quick.