I know this can be done with mvc2, but is there any way for visual studio(2010)/resharper(6) to check for errors on aspx pages at compile time and halt the build? Resharper
Yes you can. The following steps will cause .aspx files to be compiled as part of a normal builk invoked by the IDE, no Resharper plugin required.
Source - Compile Aspx pages at compile time using the AspNetCompiler build task