You always have problems with CS, don't you? Post your specs, it might help.
First of all, try different video drivers.
Guru3d.com has some good ones. It might just be a bad driver installation or something. I remember this happened to me once--I can't remember exactly what the problem was, but I know I fixed it somehow.
Rename all your configs (including config.cfg) before you start CS.This'll load Counter-Strike with fresh new config files, so anything that was in a config file that might have been causing problems before should go away. If this works, find out what's causing the problem. If this doesn't work, change your config files back.
Also, try this: right-click Counter-Strike in the Games menu, click Properties, and open launch options. Add
-heapsize XXX where XXX is half your RAM (so if you have 512MB RAM, you would put -heapsize 256 here). The heapsize is only 64 by default and this could help if you have a low amount of RAM.
If that doesn't help, try running CS without any background programs. As I have noticed, some programs (like adware or file sharing programs like Kazaa) can bog down your games, causing slow connection speeds or freezing like you mentioned. Click START, RUN and enter MSCONFIG and click the Startup tab. Click Disable All and then restart your computer. Run CS and see if the problem goes away. If it does, then there's a program that is causing problems. If it doesn't solve the problem, then you'll probably want to re-enable the startup items in msconfig. Oh, yeah--and you might want to run
Adaware, too, so that you can scan for any of those little adware programs that are hard to get rid of.
I can think of tons more reasons CS would freeze like this, though. Try these things first.