The edited one has 8GB RAM. So i7/8GB/500GB/1GB
yep, the 500GB is slightly lower, but your offsetting that with an i7 and for the most part will you really use the 500GB in your laptop anyway?, plus its a "replaceable part" unlike the CPU.
The difference is hard to calculate or show, but yes there is a performance difference. The above is an i5 2450, whereas the Acer is an i7 2670, now the issue (well not really an issue but to try to explain) is that for the most part, you'll get faster CPU performance from Core i7 parts than Core i5.
The majority of desktop Core i7 CPUs are quad-core processors, while many mobile Core i5 processors are dual-core, but there are mobile dual-core Core i7 processors, and likewise several desktop quad-core Core i5 processors. The essential to look at is that to get better performance in each generation, buy a processor with a higher model number (e.g, a Core i7-3770 generally has better performance than a Core i5-3450).
In addition to generally faster base clock speeds, Core i7 processors have larger cache (on-board memory) to help the processor deal with repetitive tasks faster. Larger cache sizes help with multitasking, since background tasks will be ready for when you switch focus to another window. The i5 CPU has 3MB of L3 cache, while the i7 processor has 6MB. Then there is also Hyperthreading in the i7 and the "Turboboost" feature gives you higher clock speeds.
The 2GB video card essentially gives you higher resolution, not necessarily a performance boost.