Gallery upgrade to 3.4

I inherited a web site which is written in HTML & PHP, one of the modules is a photo album of alumni and events which uses Gallery 1.4.4. We recently had to upgrade the PHP to 5.4 and the upload function in Gallery doesn't work now. Should I upgrade to version 2.3.2 or 3.4. We have many photos on the site and I don't want to lose them. I am also having trouble uploading either version to our server which runs on IX Web Hosting. Any help would be greatly appreciated.