Garry's Mod Freeze at Game Start-Up Load Screen

Garry’s mod has recently begun freezing on start-up, I was hoping someone could help me. I have had the game since late 2009, and have been able to play it without any hassles. However, two patches ago, the game ceased to load at the screen with Gman. I have waited up to 30 minutes, where the game would load in about 1 minute before the problem.

I have troubleshooted this game for about 2 weeks now, I’ve made a check list of the stuff I’ve done, and of what I need to post.

Firstly, computer specs.
Windows XP Professional SP3 32bit
Intel Core 2 Duo 2.80ghz
3.25gbs RAM
Nvidia Geforce 9500GT
(Lemme know if anymore are required. I’ll provide a Dxdiag if needed. I am running DX9.)

CPU and Graphics Card are updated to be current. As are all game files. I have verified Garry’s Mod’s cache, and defragmented it. I have also verified and defragmented the Source Base 2007, just incase. I have all games of the Orange Box installed, along with Counter-Strike Source and Half Life 2 Deathmatch. I have uninstalled all the addons, and reinstalled Gmod anew. I have backed-up Gmod and reinstalled from there. I have not reinstalled all the Source games, because of a shoddy net connection. I have reinstalled the Steam client (by deleting everything except for the Steam.exe and the steamapps folder).

Ok, steps I have taken. All other Source games open properly, Gmod freezes even with the advanced lines -windowed, -dxlevel90 or autoconfig enabled (I have also attempted it with a combination of the lines).

It is impossible to end tasks or alt-tab whilst the game is frozen, as the game window appears to remain in the foreground even when the program is minimized (e.g. if a text box is opened in the background, and I alt tab with Garry’s Mod open, my cursor changes into the text cursor.)

As far as I can tell, the game freeze could be graphics related, as the load screen remains even when minimized, and other tasks can be performed in the background. A graphic driver rollback has been of no help.

I apologise for the wall o’ text, but I would REALLY like to play this game. I appreciate any help or advice, and thank you in advance.

tl;dr Halp, I’m blaming a patch.