Profile for games?

I have a DELL Inspiron 8100 with a 32mb video card at 1024 X 768 , 128MB 1GHZ 20GIG HD, I use for work and limited home use for games etc which other users will also be running.
Firstly is there any point creating a profile/User account that I can configure to run the games quicker better limiting effects on work account.
Secondly if this is worth doing any suggestions any tweaks modifications I can do to make this worth while, no office apps internet mail will need to be used