Usually, yes. But mobile processors are very expensive, so it usually isn't cost-effective to try to upgrade it. Make absolutely sure you buy the correct processor for your socket, as there are many similar but incompatible sockets.
I believe I read somewhere that the Intel Celeron line was the equivalent to the sempron line
celeron
no
I recommend a laptop with a processor of Sempron or Duron, depending on your tastes. Duron is an intel-brand, however Sempron to my knowledge is cheaper, and does the job. Additionally, I'd say at least with the specs of 2 gigs of RAM. That should be a cheap buy and fit your purposes.
I7
Currently the Intel i5 processor is the most famous processor being used in PCs and notebooks. You should look for a laptop with this processor, which will speed up everything you do.
if i am not using laptop for games which processor will be best for me out amd 6 and i3. thanks
The Pentium III was a processor found in many computers, both desktop and laptop, in 1999 and early 2000s.
It has a motherboard-integrated graphics chipset by Intel: Intel Graphics Media Accelerator 4500MHD
yes
Centrino
Celeron for Intel and Sempron for AMD