Whenever i try and host, it keeps loading. It doesn't stop and when i try to alt tab it won't let me. I have to restart in order to get out of the game. It just keeps loading and loading, even waited 5-10 mins and it won't stop loading, nor will the game start

my specs are:

CPU: Intel Core 2 Duo 2.2GHz
Graphics Card: Sapphire ATI Radeon 4850
2 gigs of ram
Windows XP