Virus detection Trojans, Backdoor Hupigon

[lexus300]

Hi Pros out there,
Help needed badly for viruses detected. Hardware; laptop Dell Vostro 1500 iWin XP, installed is Avira Antivir, Adware, Spybot
Problem is virus detection in files and drives, large number of Trojan Script 23795, Trojan Generic 1090461 and Backdoor Hupigon.
Have run through with PandaActiveScan and BitDefender most of the findings were deleted except the Trojans for which disinfection failed.
Any advise how to remove this?
Log list as pasted below
Virus Detected
Trojan.Generic.102924
2
Trojan.Agent.AJBQ
2
Trojan.WSPatch.B
2
Trojan.Generic.160525
2
Trojan.Generic.185193
1
Trojan.Generic.91963
3
Backdoor.Generic.27044
2
Trojan.Generic.179662
1
Trojan.Generic.103201
1
Trojan.Generic.104136
2
Trojan.Generic.108647
4
Trojan.Generic.104984
2
Trojan.Generic.93270
1
Trojan.Generic.171905
2
Trojan.Generic.279006
2
Trojan.Generic.161680
2
Trojan.Generic.144642
2
Trojan.Generic.161593
2
Trojan.Generic.144654
2
Trojan.Generic.213888
3
Trojan.Generic.102337
2
Trojan.Generic.86101
2
Backdoor.Hupigon.17830
2
Trojan.Generic.164455
2
Trojan.Generic.103527
1
Backdoor.Hupigon.20185
4
Trojan.Generic.102746
2
Trojan.Generic.109461
3
Backdoor.Hupigon.18569
1
Trojan.Generic.161575
1
Trojan.Generic.160101
3
Trojan.Script.23795
3