For ease of learning, ASP is the way to go with your scripting language.
There obviously won't be as much documentation on ASP.NET, since it's fairly new (and to me it seems a lot harder, but to be honest I still haven't had much time at all to devote to it).
As for SQLServer vs. Access - IMHO database stuff is database stuff... I haven't truly mastered it yet, but I really don't see where SQLServer is any harder/easier than Access, since they both use SQL (Structured Query Language).
P.S. Regarding my last paragraph, I'm pretty sure that would apply to MySQL as well, since it also uses SQL... database stuff is all pretty similar... so I wouldn't let that stop ya.
If you want the fastest, use MySQL. I haven't had a chance to try it yet, but I'm itching to!
Just another 2 cents worth ;)