unable to help i'm affraid
You say you are being asked for a user name & password when downloading shareware and freeware. Well, I can't give the answer to that question but I can offer some advise.
Is the password & user name requested by your site or company firewall?
If its the website then you'll need to sign up with them and get a user name and password, if its the firewall then speak to your network administrators to address this.
Therapy is expensive, popping bubble wrap is cheap, you choose.