Which is the better antivirus?

avira antivir personal edition 8.1

or

avg antivirus free edition 8.0

in terms of virus detection, features and system resource usage ?????

Which is the better antivirus?security

Avira has much better virus detection. That is a FACT (http://www.av-comparatives.org/ ). Features are pretty much the same; AVG has email scanning but that doesn't really give it an advantage because Avira will stop any viruses as soon as they are started. Avira in my experience uses far less resources than AVG. It's currently using around 10 megs of memory on my machine, very low.

You will, however, see many people say AVG, as they know no better, and like it because it rarely gives them warnings (it never detects anything). Avira wins.

A side point: avast does not have scheduled scanning.

Which is the better antivirus?trojan

Between those two, I would have to say AVG Anti-Virus Free 8.0. If you are looking for solid freeware, I would also check out avast! antivirus 4.8 Home Edition.
avg, because if you wish, you can use a second and not have it interfere, (e.g. avg and avast)
avg antivirus free edition 8.0 is the best in my opinion. avg saved my computer twice from trojans. It's easy to use and detects all kinds of viruses fast :D
Well, I used both, as I used Norton in the past ,and regret it, and AVAST just till 3 days ago.