I HAD Premiere Pro 2 installed, but my PC experienced a motherboard failure, which also took out the hard drive. This happened over about 2 years ago. I have never been able to get a reinstall to work.... and yes, I have requested help from @Adobe_Care before. My serial number is still active. RIGHT NOW, I have Premiere 6 installed....simply because I was smart enough to get a CD-ROM instead of downloading (as I did with Premiere Pro 2). Now, I'm buying a new Windows 7 machine and would like to buy Premiere CS5.5 but I'm not certain if I get the upgrade discount price (and what that price would be)...and whether or not I'm going to have issues installing "upgrade" software on a new machine. I love Premiere Pro 2, but the issues I've had with the inability to get support is really frustrating me.
Yes, you can get upgrade pricing for Premiere Pro CS5.5 if you have Premiere Pro 2.0.
If you go to the Adobe Store and choose the Buy link for a product, you are asked what version you already have, and when you choose Premiere Pro 2, you'll see the price of the upgrade. In the US store, the upgrade price showed up as $299 when I checked just now.
The upgrade is just a price break. It's not different software from the full version. So you can install your new software on a new computer.
Do note that you need to have your qualifying serial number to be able to install an upgrade product... the product is the same as full retail, the install process is different
If you do purchase by download, you now know to immediately write all download files to CD or DVD as a backup