Port scan/hacking attempts

I have recently been inundated with port scans which my firewall is catching and says are major hacking attempts. I used System Suite Pro 8. I have an HP pavillion with Windows XP media Center OS. These hacking attempts seem to be on some kind of schedule, but at other times seem related to specific websites or types of sites. I am trying to figure out if it might be some kind of spyware that has infected my system. I have run all the updates and scans for my System Suite, free Ad Aware, Spy-bot, Panda Scan and Trend House-call. none of them are finding anything, although one did find a Zlob trojan. I thought I had managed to remove it, but maybe not. Can anyone help? I am afraid this issue could become dangerous. Also, if I am trying to access a web page when one of these scan attempts occurs, it knocks my system off line. My backtrace attempts say it is originating from a couple of different IP addresses. 68.105.28.12 (11) and 68.105.29.11. I have read several of the past repsonses to port scan attack worries, but still feel that this is something else, since it occurs so regularly and on a sort of scheduled basis.

Help?

Rfglasart

 

Thanks. I have contacted Cox and complained and was assured someone would look into it and get in touch with me. Nothing so far. Any idea why it would be so persistent and why did it just start happening for no apparent reason? Should I assume Cox is trying to monitor my activity? I mean, specifically looking at me or do you think it is something that is happening on a broader scale? any way to tell or find out?

Thanks again for the reply.
Rfglasart