I've got the 3.5 PHB in front of me

[Voadam]

The SRD doesn't have everything you need. It's missing some monsters, character creation and advancement rules, and flavor text that sometimes is more than just flavor. If you just use the SRD, you will be missing some needed information.

Eh, all you'll miss is stat generation, the order of doing things during advancement and xp. The excised monsters are mostly iconic D&D but I've played since the eighties and this weekend was the first time I'd ever seen a slaad (one of the WotC IP monsters not in the srd) in an actual game. You can play a fine D&D game with just the monsters in the srd.

XP is the toughest one to come up with your own reasonable replacement system, but it is certainly doable.

I pretty much only use the DMG for instant npcs, character wealth per level chart, and xp, all the items and hazards I normally refer to the srd.

 

[Spiteful Dwarf]

ROY IS DEAD!! DEMOGORGON HAS STOLEN HIS ESSENCE!!! ALL HOPE FOR THE FUTURE IS LOST!!! (well, for the next month or so...)

 

[Piratecat]

Since someone has started a clean thread for more Q&A, I'll close this and provide a link!