Hi Molly,
Well, if you are going for new, you will more than likely have to go with the new Vista operating system, I am running PC's with both XP and Vista and I think it can be said that Vista is not probably, as bad as you hear. However, look at the Home Premium edition as a minimum, don't go with the "Basic" edition.
If you do go with Vista, you will need a minimum of 2 GB of RAM, better even with 3 or 4 if you can get it.
I would also look at computers with a minimum hard drive of 200 GB, the vista operating system is huge and uses a lot of hard drive space.
Not sure whether you are looking at a desktop or a laptop,the new core 2 duo processors are good and allow you to run different applications at the same speed, not really that important though depending on how you use your PC.
Over here on this side of the island, the East, Cartridge World are very cheap for PC's, laptopwise, Carrefour and Orphanides are quite cheap too, I would however, try and source a local shop where you can go back should you have a problem. Spyros, on the CL Forum has a shop and I have found him to be very knowledgeable and helpful, you can contact him here.
http://www.pcrepairs.com.cy/ Hope you found this helpful, by the way, I'd ditch Internet Explorer and use Mozzilla Firefox, much better and safer. You can run both together on your computer, if you install Firefox, you can import all your contacts from IE, remember also to back up your address book in the CSV format, (Comma Separated Values ), save you writing them all out again.