Thanks for the reply Dave,
I have both of those programs and have been running them - SAS is always on, and the Malwarebytes has been in frequent use since this problem came up. I also have HijackThis installed. At first, they found some things
I have been slow to respond because I have been busy, and the system is otherwise doing well, so I have just been living with the problem. The few searched I have needed, I just turn off the Avast web client. Obviously, I am a bit hesitant to continue to do this. I am aware that sometimes viruses will hijack the browser, sending the searches to odd locations. So far, everything I have searched seems right (no porn sites when foodnetwork was the link I wanted 
I don’t know if it is helpful, but I have included 3 logs: Malwarebytes from June 14 when it cleaned the problem, Malwarebytes from today, and HijackThis from today (next post). Unfortunately, I cleaned the AVG logs along with the program. AVG also found some issues and cleaned them. I remember somewhere along the process that a warning was issued when the infected files were cleaned. The warning was to the affect: “These are Windows Files, are you sure you want to delete them?” I did.
Malwarebytes’ Anti-Malware 1.37
Database version: 2255
Windows 5.1.2600 Service Pack 3
6/14/09 1:51:38 PM
mbam-log-2009-06-14 (13-51-38).txt
Scan type: Quick Scan
Objects scanned: 96331
Time elapsed: 23 minute(s), 36 second(s)
Memory Processes Infected: 0
Memory Modules Infected: 0
Registry Keys Infected: 0
Registry Values Infected: 0
Registry Data Items Infected: 0
Folders Infected: 0
Files Infected: 2
Memory Processes Infected:
(No malicious items detected)
Memory Modules Infected:
(No malicious items detected)
Registry Keys Infected:
(No malicious items detected)
Registry Values Infected:
(No malicious items detected)
Registry Data Items Infected:
(No malicious items detected)
Folders Infected:
(No malicious items detected)
Files Infected:
c:\documents and settings\GB\nah_hnsp.exe (Trojan.Hanam) → Quarantined and deleted successfully.
C:\Program Files\Mozilla Firefox\chrome\amba.jar (Trojan.Hanam) → Quarantined and deleted successfully.
And, here is my latest log for Malwarebytes:
Malwarebytes’ Anti-Malware 1.38
Database version: 2358
Windows 5.1.2600 Service Pack 3
7/1/09 9:18:39 AM
mbam-log-2009-07-01 (09-18-39).txt
Scan type: Quick Scan
Objects scanned: 101823
Time elapsed: 18 minute(s), 7 second(s)
Memory Processes Infected: 0
Memory Modules Infected: 0
Registry Keys Infected: 0
Registry Values Infected: 0
Registry Data Items Infected: 0
Folders Infected: 0
Files Infected: 0
Memory Processes Infected:
(No malicious items detected)
Memory Modules Infected:
(No malicious items detected)
Registry Keys Infected:
(No malicious items detected)
Registry Values Infected:
(No malicious items detected)
Registry Data Items Infected:
(No malicious items detected)
Folders Infected:
(No malicious items detected)
Files Infected:
(No malicious items detected)
–
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