@NogDogNov 02.2009 — #Simply echoing a variable takes very little time at all -- we're probably talking something you would measure in microseconds.
To find out where your delays are would require a much more comprehensive code review and perhaps some metering and other performance testing to isolate the actual bottlenecks. Some of the common performance issues are inefficient database usage (poor data design and inefficient queries), accessing external data via HTTP requests, loops that spawn new processes of some sort on each iteration, reading large files and manipulating their data, etc.
Simply including one include file and doing some echoes should not be an issue (unless there is something "ugly" going on in that include file).
@MindzaiNov 02.2009 — #If your site is slow, almost certainly by the far the biggest bottleneck will be HTTP requests, not PHP code. Make sure you have proper expires headers set on your static content.