The main difference between Intel and AMD is the kind of user.
If you're a disaster in the workshop you might want to consider
taking Intel, Since they're hard to wreck and stay cool. If you're
a "mister do everything myself" you might want to take AMD.
Let's get a rumor straight: Pentium's are NOT more stable than
AMD's. It's all about the end-user. If your AMD is unstable you
should blame your hardware configuration or your messy hd.
Pentium's 4 overclock nicely and stable and need no hardware
adjustment in the form of voltage modification or CPU Bridge
connecting. AMD overclock nice as well, Though not so well
as Pentium's and require certain hardware adjustments,
However, AMD's are considerable cheaper than Pentium's of the
same speed and thereby offer a nice deal for people low on
budget.
Pentium3: Is rather cool, Needs a finger modification to
overclock, Is quite cheap (if you can get it

)
Pentium4: Is very cool, Can overclock very well, Is rather
expensive.
AMD Duron: Is quite warm, Can overclock very well, Is extremely
cheap.
AMD AthlonXP: Is quite warm, Can overclock a little, Is very cheap
for it's performance.
AMD Barton: To my knowledge the same as the XP but has
256 Level2 Cache and can run at a 166MHz FSB.
Hope to give you an idea with this

.