Vista - IE 7 Slow Downloads

I am experiencing slow download speeds and am stumped as is my cable company. Any ideas would be helpful before I do a system recovery, which I am trying to avoid. Pages used to download in 2-3 secs now take a half minute.
Here are the stats:
Computer: Intel Dual Core 2.2, 3gigs ram
Cable tested download speeds with current modem 6-13mbs according to Speedtest.net.
I have tried the following:
Cleared cache and temp internet files, disabled all add ons, defraged system,4 different internet virus scans along with Trend Micro downloaded and working, no viruses or malware found through Adaware and Spybot, tried without the router, tried Firefox, Safari, IE 8 and Chrome with no difference in speeds, no packet loss on pings through modem, tried four different registry cleaners. Only one firewall installed and only one antivirus installed at a time. I have also tried without any antivirus installed with no change. My old laptop with a Celeron and 512 ram is faster and does not show same problems through the wireless router. Is it time for system recovery? I appreciate any ideas. Thanks very much.
Robert

have you tried a tracert just to see exactly where your isp is routing your searches and if they are getting "hung up" anywhere

click start then run and type cmd then return in the resulting window type tracert then the address you want to trace too eg

tracert www.google.com

then hit return , copy and paste the results here

Archie,
Thanks for your reply. Here is what came back:
Tracing route to www.l.google.com [74.125.95.147]
over a maximum of 30 hops:
1 1 ms 1 ms 1 ms 192.168.0.1
2 * * * Request timed out.
3 9 ms 10 ms 8 ms ip58-2-11-29.ph.ph.cox.net [58.2.11.29]
4 10 ms 11 ms 11 ms 70.169.73.53
5 23 ms 20 ms 21 ms langbbrj02-as0.r2.la.cox.net [58.1.1.231]
6 21 ms 21 ms 35 ms 216.239.46.180
7 37 ms 33 ms 35 ms 72.14.238.130
8 91 ms 75 ms 68 ms 209.85.242.210
9 68 ms 69 ms 71 ms 209.85.243.116
10 67 ms 75 ms 68 ms 209.85.241.35
11 73 ms 69 ms 74 ms 209.85.240.49
12 75 ms 70 ms 76 ms iw-in-f147.google.com [74.125.95.147]
Trace complete.

I finally gave up and did reinstall of operating system. All is fine.