i am pretty sure Pentium is better than celeron.
is this for a desktop? im assuming?
celeron is mostly seen in laptops, and i dont know if its dual core.
when comparing CPU's you want to look at a couple things
1. CPU frequency. the pentium is a 2.7 and the celeron is a 3.3. if they were both 1 chip set like if they were both pentium then the faster frequency would be faster
2. cores. 1 core/dual core/quadcore
the more cores the more multitasking. multi core processors usually have lower freq because they get hot. But the task usually "splash" over to other cores while in dual core CPU's they cores do more work.
3. finally for everyday use the size. the lower the chip size the better. the newer ones are 45 nM but those 2 you listed are older and i dont know what size they are sorry :*(
now dont get confused. the pentium and celeron are both different types or chips. just because the celeron has a faster freq doesnt mean it is faster. there are other factors. like i said in "1" if they were both pentium then the higher freq would be faster, if they were both celeron the higher freq would be better. But they are 2 different chips. the pentium being the newer faster one.
what purpose are you using processors for? gaming or home use?
for any situation, the Pentium at 2.7 is better.
why those two? look into the new lga 775 core 2 duos or the even newer i5/i7 for home use.