You will be able to do it, but you won't be able to do anything very adventurous. A 2.2GHz Sempron barely squeaks in over the minimum specification for FL10 and the single core will quickly get flustered if a lot starts happening. That will limit number of tracks, use of effects and instruments.
Current suggestion for ideal balance of performance against cost is i7-2600K or i5-2500K and 8G of RAM they suggest is enough (but even 4G is enough for most people):
On passmark CPU Benchmarks for example, the LE-1250 scores 549, the i5-2500K scores 6,743.