[Techtalk] Group Permission Security Question

[TechChiq]

I want to set up so that my main account on my linux box (the one I do
all my normal work in) can also access some files that have group set to
"root" (like when files were transferred from another drive I don't know
how the group didn't get set to write). I keep having to make superuser
windows or terms for stuff. Is it bad security to set a certain user's
group mode to "root"? 

Also, I have a couple folks that may use my machine so I want to make
accounts for them too. One would be my boyfriend, who knows little about
computers (he's learning :) so I would like to set up something where he
can't blitz nothing. Of course I wouldn't set him to root group! LOL!

Then there's another friend of mine who we all call "The Wizard" (what
his wife nicknamed him). I would like him to have his own account (not
root) and have superuser priveledges to do what he needs to in case he
needs to fix something or show me how to fix things. How would I set up
his account?

I'm still a bit lime-green on this permission thing...

-- 
TechChiq
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Linux User # 331707 Machine # 216034 (http://counter.li.org)
Pink Tie 9 (RH9 clone), Kernel 2.4.20-6, KDE 3.1, Wine 20031016
Win98SE (dual-boot)