I'd agree with Lemur...Pentium Ms (or core as it's known nowerdays) is great. Fast and relatively economical on power. Throw in a decent card (like 6600 mobile or whatever) and you should be go for small resolutions. In my opinion though, it's not worth mixing the two because you usually endup with comprimises that are just too annoying unless you have enough budget.

I personally quite like Acer's range (got one) but that's just me.