1) I know there is counterstrike and counterstrike source. I purchased "Half Life Counter Strike" a few years back from the store. Will counterstrike source work with the key that I have for regular counterstrike?

2) How do I remove the server ad banners and other ad banners? The reason is because I removed Internet Exploer using nLite, but sadly every time steam tries to load a graphic from these servers, it opens up firefox and the screen switches view to firefox. Is there any way I can fix this? I'd really rather not have Internet Exploer, but this problem is annoying too.

I'm pretty sure the answer to #1 is no, you might have to buy HL2 for that. But, then again, I'm not a that much of a CS gamer, so I'm not "too" sure.

That ad problem seems rather odd. If you havent already, turn on popup blocker in firefox.

The problem with the ad thing is since Internet Explorer does not exist, firefox is loaded instead to display the graphic that would otherwise be displayed in the IE engine.

You can remove IE, but keep the IE Core to fix this problem.

Don't wanna do that :/ I might as well just remove the icon from the desktop. But I did find a workaround: blocking steampowered.com/.net gets rid of most of the ads and running in windowed mode removes the problem of the game screwing up.

Whatever works for you.