Adware vs spyware--both bad, right?!

What's the difference between adware and spyware?

I assume both are bad and I do NOT want either of them on my computer; right?

Do I need separate programs to remove each of them? If so, which should I use?

Right now, I'm running Windows 7 home premium, Microsoft Security Essentials' firewall, and Microsoft Security Essentials' virus scanner, but nothing more. What else should I get and use?

Thx.

Tom

ps. I've read the general security cookies and help msgs locked at the top of this forum, and I'm enough of a newbie that I still have the questions I've posted here, so please, help me out.

 

OK. Thx.

I'm curious what kind of "browsing habits" might suggest I use belt AND suspenders.

My typical computer usage is pretty vanilla. Other than Microsoft Office, which doesn't go online as far as I know, I mostly check email with gmail (weaning myself off hotmail); updating stock prices through Fund Manager, which I've got set to use yahoo/finance at the moment; travel message boards and related sites such as Rick Steves, Lonely Planet, TripAdvisor, and Fodors; the usual hotel booking sites and travel sites such as hotels.com, kayak, Delta Airlines, occasionally Expedia; a wide range of financial sites where I have money invested, such as my bank and mutual fund companies; a couple genealogy sites such as Ancestry or the LDS Family Search site; etc. My wife also uses hotmail, Office, and her own set of hobby-related websites (gardening, storytelling, etc.), but she doesn't download videos, music, or pictures, either, as far as I know!

I never use things like Facebook or twitter or download music or videos, although I do occasionally listen to a playlist of my favorite classical music on youtube.

Does any of this put us at extra risk such that using malware.... in addition to MSE would be a good idea? Or can I leave well enough alone?

Thx.

T