UNIX for Advanced & Expert Users

i am on a fedora 2 (2.6.8-1.521) kernel i686
and i have several process that I keep open at all times when the system is on and off and a few more when the system is on.. amongst which are three terminals that always log in with 6 open windows on the first terminal, three on the second terminal and emacs on the third terminal and the odd xterm.. also I keep my xmms an d noatun apps open.. according to a book by paul sheer Rute Expo the niceness of certain processes can take up cpu time on the system and slow down the overall process time... my first question is:
if I keep all my processes open as usual and renice them to +19 or so would that make my system more efficient and faster since it has slowed down a little.. and also how would i go about renicing them.. I have read the technical part but did not comprehend the verbatim very well..
any feed back welcome
thanx moxxx68
ps mozilla is running too 80% of the time

If your system is cpu-bound (look in /proc for cpu information)
then lowering priority will help - if those processes actually use cpu.

Usually systems slow down gradaully because of disk issues, issues like fragmentation or low free disk space. The other issue here can be real-time processes - these processes don't play fair when it comes to sharing the cpu. They hog it. If you have added real-time processes, like some types of packet sniffers running all the time, then you may have this problem.

Low free memory is another thing to check. Pagefile activity may be hgh in this case.

Basically you have to gather lots of system data, before you start guessing and randomly changing things that may not need changing.

thanx for the feedback
moxxx68