Well i can say that my comp is relativley safe,but ive just cleaned up alot of adware and 2 trojans(though i downloaded them BECAUSE I AM STUPID AND NON CAREFUL),so i would like to an expert is Avast a good antivirus or do you suggest another?Can you also recommmend me also an extra antivirus program(Except Zone alarm,i have that and its working briliantly)

There are many good, free AV applications for the computer user (see the link):
http://www.bleepingcomputer.com/forums/topic3616.html

I have used Avast and AVG, but the former at least on my computer with its configuration, was slower than AVG and used more resources. Other Members have had good experiences with Avast.

However, it is best to have only one resident AV on your hard drive, especially if both attempt to provide real-time protection. Running two concurrently can not only slow down your computer, but produce serious conflicts. Just as importantly, it can be confusing when one AV discovers the virus definitions of the other and wants to quarantine them.
There is always the option of using one of the many good on-line AV scans to double-check the protection your own AV is providing.

Regards,
John

i use avast, and it works fine for me. i agree with jgweed that avast does seem to use a lot of resources sometimes, especially when its automatically updating itself. on a superficial note, i'm not particularly fond of avast's layout nor the way its way of alerting me of malware (usually by giving me a large pop-up notice and a voice message) but its effective enough. i think its realtime scanner is really good

Never liked Avast! I preferred AVG, low impact on system, clean interface, easily navigated and great all round protection. Good bang! for the buck. The new AVG Anti-Malware product also deals with adware/spyware/malware.