Since you've read the prior discussions and hopefully learned that registry cleaning is not about speed and rarely helps any issue, why do that?
As to which apps are needed, ONLY YOU can know this. For example I really need the Intel WiFi helper apps. Your machine might be some desktop with Ethernet so YOU KNOW YOU can disable those.
For each app, YOU are the only one that knows. Some folk think this is something they could ask others.
I have run CCleaner and while it has helped speed I got rid of CCleaner as it could not clean the registry as advertised. I ran Uniblue Reg Booster same result. I ran AVG free trial and came up with many reg errors and many junk files. I manually deleted these reg errors and files and some reoccur but far less than the above apps. My question is Which apps are necessary for the startup menu? I have done all I care to do with IE9 and have it unchecked in the windows component section of Uninstall Programs. I find Windows 7 to be a poor followup for Windows XP!