Is there an Anti Virus that uses minimal amount of memory?

[Derfdog]

Hello

I have resurrected an old Acer Aspire D255 netbook to take on a trip instead of my laptop.
I am upgrading the memory from 1 to 2 gig ram, installed a 60 gig SSD, loaded Win 7 32 bit Home Premium.  Everything except the 2 gig ram I had laying around my house collecting dust and with Win 7 it actually runs pretty good.

I am looking for an Antivirus program that uses a minimal amount of memory (2gig is not very much nowadays).  I wont be doing much with the netbook mainly surfing and some word processing, but will be connecting to public WiFi.  Will the new types of Antivirus automatically adjust to the amount of available memory?

[SuperDave]

I recommend MicroSoft Security Essentials. It's lite weight and unobtrusive.

MicroSoft Security Essentials   All versions and all languages.

[Hilly8]

Thank you so much for the app recommendation and to this thread!