My computer has XP and 4 accounts 1 for each member of the family.I have installed Limewire basic onto the computer but can only be accessed from my account and does not even show in programs on any of the other accounts.However if I say go into my sons account and access control panel it is there.How do I get it so that everyone can access from their own account ?

Simple, create shortcuts from the main admin account & copy/send those to the user accounts of each family member. I'd send one to desktop, & possibly also one to start menu on each account. Each user will by default save their files in their own account area & their separate settings will also be saved into the individual user account.
eg: default save location: C:\Documents and Settings\"your account name"\Shared

LW preferences folder with individual settings saved for each user: C:/Documents And Settings/your_username/Application Data/limewire