Some more basic advice (sorry it you know all this already but if you are new to computers you may not).
As I said, be VERY wary of clicking on any link in an email, it may take you to a dummy web site, or maybe a web site contaning a virus.
NEVER give out personal information when prompted to via an email. A bank will NEVER ask for your password, paypal will never ask you to "verify your account details".
DONT believe every email you get. You have NOT won the lottery, you have NOT won a free holiday, you have NOT got a rich uncle in Canada who has left you lots of money.
These are all scams just trying to get money out of you. There is always some "upfront" fee to pay before getting your hands on the money (admin fee, local tax etc).
Be wary of an attachment that is sent along with an email, particularly one from a person you dont know.
If may say "click on the attachment to see a picture of the Easter Bunny", or "Brittney Spears in the nude", or whatever).
This attachment will nearly always have a virus on it.
Make sure you have anti virus software installed and run it regularly (or better still a full security suite).
Make sure you run Windows Update on a regular basis to keep Windows up to date.
Try to have a firewall installed on your computer.
Unfortunately using a PC connected to the internet is now a rather dangerous place.
There was a guy in Scotland the other day who lost his HOUSE because he replied to one of those emails that said he had won the lottery.
http://news.bbc.co.uk/1/hi/scotland/south_of_s cotland/7979595.stm