HELP!!! Can't remove my 5 viruses!

[Teacher]

Can anyone help me??? I was stupid and decided Avast! was taking up too much room on my computer and decided to delete it. I thought I was smart and would be okay without it! Well, now I've got 5 viruses. I have reinstalled Avast! and it says there is an error when I try to repair the files. Listed below are the virus names. Please help me get rid of these if you know how.

Win32:Lalus
Win32:Ncasespy
Win32:Ruledor
Win32:Istdnldr
Win32:Trojan-gen

Thank you so much!!

[Eddy]

Run a boottime scan and let us know if that solved it.

[markus0r]

hmm, did avast! find these viruses? then it should be able to delete it (if im right hehe)

[techie101]

Teacher,

Well, I guess the Teacher has been "taught" or rather "caught" by viri.  

Ok, go to this site and follow the instructions for the virus names you mention:
http://www.sophos.com/support/disinfection/trojan.html

And do me a favor.....Put Avast back!  
Then run a full scan to make sure the system is clean.