PC locks up (10-60 seconds) when I save something

Hi,

First post, and I'm really wiped from work problems, so I apologize in advance if I miss some information necessary.

I have a circa-2005 Dell Dimension, 3.0Ghz, 3 GB RAM, XP Home SP3 with Norton 360. I have a lot of multimedia stuff on here (scanning, printing, video editing, etc), but the PC has been fine, until about 6 nights ago, it started just locking when I clicked "save". Whether I was saving a Photoshop edited file, an image off the internet or via email, even some Office docs.

I did a quick check on google and saw a thread that said that some MS updates conflict with HP printer software, and that may cause this (A Norton complete scan found an unused registry entry from HP and deleted it, not sure if that is involved), but there really haven't been any Windows updates that I noticed recently, so I think it's a virus/worm/trojan? I ran Malware Bytes and the MSRT from Microsoft in safe mode and didn't get anything.

I have a lot of photos to edit in the next few days, and it would take me too long at this point to reformat and reload everything, so I hope someone can make a suggestion. The PC isn't running slow on any other area than saving/downloading (even clicking "save" on an Excel file I email myself from work locks it up).

I'm trying to find the printer software disk, and when I do, I'll try removing the HP software and see if that helps.

I don't do gaming or torrents, if that matters.

Thanks in advance,
Rich