You should be careful about what you Force Close. While you won't break the phone, you can certainly cause it to crash or reboot by FC'ing the wrong thing. Also, you should not have to do this except in the abnormal event that an app is hung or hogging resources. You'll find even stopping processes, many of them will just start back up. It's how most operating systems work now, since there are lots of background processes going on to sync up data like mail or weather and stuff.
A better solution would be to post back with what you consider a "horrible" battery life to be (one man's horrible battery life is another's great batter life) and perhaps post a screenshot of your battery usage screen (Menu -> Settings -> Battery) so we can see what's using it.
There are many things that can contribute to battery life, including (but not limited to) how much you use the phone/display, what you're doing (videos/gaming/just checking Facebook) how bright it is, what you have enabled as far as radios (Bluetooth, GPS, mobile data, wi-fi, NFC, etc), what you have installed, how often you have apps or widgets or notifications pinging for data (like checking email or updating weather), etc.
Regardless, you shouldn't have to be in closing tasks and processes, at least not very often unless you have a problem with an app not functioning correctly (or it was just coded poorly).