Upgrade crankset

What's wrong with your current chainrings?

If you want different gear ratios, just change your cassette.

I could be complete wrong here, but compact cranks use a 110 bottom bracket so I'm not even sure you can put standard rings on the crankset.

your crank arms may not be interchangeable from compact to standard chainrings...check this with your LBS before buying.

some compact cranksets have different spider arm spacing and can't accept standard chainrings.

Compact cranks usually have a 110mm BCD, and standard cranks are 130mm.  It's possible to find 39t and 52t rings with a 110mm BCD, but I think you have to shop around for them or get them special ordered.

It's probably just as easy and cheap to swap the entire crank, as long as they can both use the same bottom bracket. 

But easier still to just switch cassettes--I think that's what most people do to adjust gearing to specific terrain.

And unless you're already strong enough to spin out of your largest gear with the compact (50-12?), you wouldn't really gain anything by changing your gearing at all.

Edited by tjh 2009-07-17 10:11 PM