Rebuilding a Joomla site with wordpress


Spoke about this in live chat yesterday with Alex, but basically I'm looking to rebuild my old Joomla site Link removed at members request in Wordpress. Only problem is, that site has lots of reviews on it (using jreviews) which need to be transfered over to the new site somehow. I guess I'll have to do this manually? So basically, I need to keep the old site functioning until I have the new site finished.

Can someone please give me step by step instructions on how I would install the new site on a subdomain (as Alex suggested). I use hostgator, and usually cpanel to get into my files. Is there an easy way to do this without affecting the current site, and then will it be a major ordeal to transfer it to the ********* domain once completely finished? (I won't have support here by then).

Initially I said to Alex I will leave this until I can afford to buy another subscription to WPMU, because i don't feel totally confident and don't want to destroy the existing site, but I originally did want to get this other site rebuilt whilst under this subscription, things have just taken me a lot longer than expected to get thehouseofdog up and running, it's been a very steep learning curve for me and I've had to ask so many questions which have sometimes taken a good while to get answered.

But if I can just get this installed on this subdomain today before my subscription expires tonight, at least then I can manually download the wpmu plugins I need and install them and make an attempt to get the site ready to transfer on my own. I would just like a little help getting this installed if possible?