I personally have had better experiences with Intel graphics for HTPC use. The drivers seem to be more stable overall whereas ATI/AMD traditionally seems to have had a stable driver and a bunch of duds. The Intel configuration is generally much simpler and easier to follow than Catalyst.
The good thing for you is that you’ve already got the 5450. You can try out Intel first and if for some reason you are not satisfied, you’ve got a backup plan.
