Problems trying to install printer wirelessly.

I have had a HP deskjet F4500 connected to my iMac (running Lion 10.7.5) by usb for quite some time with no problems. Just today I thought I would set it up wirelessly so I can print from my ipad from anywhere in the house. Big mistake. I uninstalled the software then tried to reinstall it using the CD rom which came with the printer. After several tries with no success, I finally got the message that the CD rom will not work on Lion. I have put the usb connection back in and now I can print from the iMac again but not, of course, wirelessly. Will I need a more up-to-date printer in order to set everything up wirelessly? I just went on the HP website for advice but, when I tried to download some software, I just got error messages and my System Prefences won't open. I have had my iMac for some 6 years but do keep it up to date and the printer is only a couple of years younger so perhaps I should buy a new printer? I would be grateful for any advice out there.

Thanks in advance

Anne Adshead

(England)