Trojan Wallet stealer protection?

[Quantus]

    Running Windows 7 ultimate. I have installed Vitualbox with >Unbuntu now I can run my Bitcoin client inside of this (sandbox?) and still back it up with Dropbox and encrypt it with Turecrypt. Do I even need anti virus on this Unbuntu install? I will only use it to send and receive bitcoins. Am i safe from the Trojan Wallet stealer

[BombaUcigasa]

A few obvious problems so far:
- Dropbox security is FAIL. One sunday they allowed ANY user to login into their account with NO PASSWORD. Otherwise their security is fail.
- keylogging on the guest can intercept your truecrypt password (no matter if you encrypt the VM or use disk encryption in the VM itself)
- screengrabbing can sniff some of the addresses, sites and other things a keylogger on the guest can't see into the vm
- physical attackers can be present, or even remote ones. Make sure you are protected against people accessing your desktop directly