Anti-virus question

I use Avast! (yarrr!!!), and while I like it in general, the e-mail checking component of it significantly slows down my e-mail program. Pulling down e-mails takes much longer than it should, and sometimes the computer will kind of freeze up for a second while it’s doing it. It’s also extremely suspicious of eFax for some reason, and I haven’t figured out how to stop it from popping up a huge warning every time I get one.

If I just turn off the e-mail component, am I at any huge risk? Most virus e-mails are pretty easy to spot just from the subject line so I never even click on them, and even if I do, I"m certainly not going to open an attachment in one.

Don’t use outlook or outlook express and risk goes down. Namely because most emails that don’t need clicking (html enabled on email client) would target vulnerabilities on the most popular clients.

I use Thunderbird