I see this posting has been here a while but just wanted to add few more references for archive use...
I think Fedora is good for most general computing needs (I often use it but mostly for workstations or just to make other guys in my team feel easy

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I also agree with mutex on trying out FreeBSD as it is very well hardend/stable flatform.
FreeBSD is an excellent choice as a single purpose servers that require stability and security(mail, web, etc.) as well as general developement platform, in my opinion.
Trustix(I think IBM Linux started off of this?), would be another one to look at as well.
Also checking on few sites like;
http://www.distrowatch.comhttp://www.linuxlinks.comshould give you more then enough choices for your needs...
Cheers,
Troy