RAID5 performance depends greatly on the RAID card (in this case, Intel's "Matrix"), but in general, RAID5 is very slow for disk writes.
RAID 0+1 would actually be more redundant (that is, you are less likely to lose data) than RAID5, and would likely be faster.
RAID 1+0 is generally thought of to be better than 0+1 because the likelihood of data loss is smaller still.
Out of those choices, I would choose RAID 1+0, however,
You are likely to get even better overall performance, depending on how you use your system, by setting up TWO arrays of RAID1. This would give you excellent redundancy and you could split the load between the arrays. For example, the operating system and related files could go on one array, applications/games on the other.
There are certain situations where RAID 1+0 is faster than 2x RAID 1 (and even where RAID5 is faster than all of the above), but these tend to be special cases such as the editing of single streams of uncompressed HD video.
The main disadvantage of RAID 1, whether in several separate arrays or in a 1+0 array, is loss of usable space, but if you have only 30GB or so of data, who cares?
Finally, other options to consider might be using one drive (or array) as a backup, keeping copies of your data (perhaps incremental backups). Four separate drives is reasonable as well, since RAID is more about uptime than about data security (assuming you make backups of data).