Synaptic Package Manger not working


I'm new to ubuntu and being so excited, I think I may have messed up computer while tweaking on it.

When I go to my synaptic package manager, this window pops up:

An error occured.
The following details are provided:
E: Type 'rem@Tabby-UBU:~$' is not known on line 50 in source list /etc/apt/sources.list
E: The list of sources could not be read.
Go to the repository dialog to correct the problem.
E: _cache->open() failed, please report.

When I go to my Add/Remove, this window pops up:

Failed to check for installed and available applications

This is a major failure of your software management system. Please check for broken packages with synaptic, check the file permissions and correctness of the file '/etc/apt/sources.list' and reload the software information with: 'sudo apt-get update' and 'sudo apt-get install -f'.

Can someone please help me fix this step by step. PLEASE :(
Thanks in advance!!
PS. i have an ubuntu 9.04 (jaunty) ...i think....

Sources list

You have messed up your sources list, so you need to edit it.

Open a Terminal and issue the command: gksudo gedit /etc/apt/sources.list

That will open your sources list in the editor called gedit.

Look for line 50 which should say: rem@Tabby-UBU:~$

Make that line ineffective by putting a # at the beginning.

Save gedit. Exit gedit.

Then in a Terminal issue the command: sudo apt-get update

Job done.