Ross,
 
There is nothing in Stuey's list that does what Defender does, nor that conflicts w/ it.  His A-V w/ Firewall will shut the OS Firewall down (I hope, not both; the W7 Firewall is pretty good, though).  But, if that A-V has no anti-malware component then Defender should be on.  That Super Anti-spyware prolly isn't needed.  Spyware Blaster is cool.
Really all W7 needs is a good A-V, a good A-M, maybe SpywareBlaster & a good firewall.  Also doesn't hurt to have some intelligence & common sense in the chair but, that's true no matter what OS.
Certainly, as I get everything back on track in my W7s but, in general, too, I sure do like having Quick Launch!!
Cheers,
Drew
"A scan a day keeps the nasties away!"