Hi,
My computer configuration is given bellow. When I install Avira antivirus, it seems to perform slow. I would like to know that why the computer slow the computer after install antivirus and what is the remedy of this computer. So you would kindly request to give me a good suggestion.

OS Version: Microsoft Windows XP Professional, Service Pack 3, 32 bit
Processor: Intel(R) Pentium(R) 4 CPU 2.40GHz, x86 Family 15 Model 2 Stepping 9
Processor Count: 1
RAM: 765 Mb
Graphics Card: Intel(R) 82865G Graphics Controller, 96 Mb
Hard Drives: C: Total - 24999 MB, Free - 10558 MB; D: Total - 16998 MB, Free - 7502 MB; E: Total - 16998 MB, Free - 16478 MB; F: Total - 7248 MB, Free - 7125 MB;
Motherboard: Dell Computer Corp., 0C7018
Antivirus: AntiVir Desktop, Updated: No, On-Demand Scanner: Disabled

Thanks,