Strange PC problem?

I working on a friend pc runing HP win xp home, pent.4,2.0ghz, 768mb ram.using dsl

1) it a rogue anti virus. i removed that with regoue pro 2) downloaded and run the follow apps. adware, ccreg cleaner,etc. it did speed things up and seems to work ok with normal cpu usage(2 to 10%) until she goes online then it get slow,slower, slowest the cpu jumps to 100%. i have noticed a process being loaded after she goes to the internet. the process is "logonui.exe" . i need help,i will try an upload a hijack txt file. i won't let this D@#$ PC get the best of me, thanks

Logfile of Trend Micro HijackThis v2.0.2

Scan saved at 11:39:32 AM, on 1/23/2008

Platform: Windows XP SP1 (WinNT 5.01.2600)

MSIE: Internet Explorer v6.00 SP1 (6.00.2800.1106)

Boot mode: Normal

Running processes:

C:\WINDOWS\System32\smss.exe

C:\WINDOWS\system32\winlogon.exe

C:\WINDOWS\system32\services.exe

C:\WINDOWS\system32\lsass.exe

C:\WINDOWS\system32\svchost.exe

C:\WINDOWS\system32\svchost.exe

C:\WINDOWS\System32\svchost.exe

C:\WINDOWS\system32\spoolsv.exe

C:\WINDOWS\System32\tcpsvcs.exe

C:\WINDOWS\System32\snmp.exe

C:\WINDOWS\System32\svchost.exe

C:\WINDOWS\Explorer.EXE

C:\WINDOWS\System32\rundll32.exe

C:\Program Files\Common Files\S?mantec\n?pdb.exe

C:\Program Files\Internet Explorer\IEXPLORE.EXE

C:\Program Files\Trend Micro\HijackThis\HijackThis.exe