Hard to say much without knowing specific details but:
Subscribing to the addon pack solely is definitely a faster way of joining. Making sure you have CSS(counter strike source) is another good idea. If you are having issues well i cant speak on them due to not knowing what they are.
Sometimes the DSL internet can slow the process down even more but that also depends on location and time of day. Some ISP companies recently have been bottlenecking connections and doing shady shit or so im told anyways.
Ram should be good.
FastDL from the server is always great to use, but i find having the addons on hand especially as a SA+ is more useful.
I would recommend you do a complete reinstall of not only the addons but your game as well, do a verify game intregrity AFTER first launch of the game and your addons have been installed.
Me personally, i run the game in a window, mainly so i can tab between screens and so on and its actually had a positive effect on performance for me.
Hope this helps.