Very Newbie Questions

[Tom - Hwy101]

I am a XP Pro User, Thunderbird - I got the extension for Thunderbird to
do PnuPG... and have the executable to Install the Encryption program.

I mainly want to ´Sign´my msgs at this point and not Encrypt, is this
possible to just Sign without a lot of hassle?
Or to setup to default that way so I don't have to choose to Sign and
not encrypt?

Thanks for Any Pointers - Tom