Vaccuming on 7.1.3

Hi group!

I've seen the page
http://www.postgresql.org/idocs/index.php?routine-vacuuming.html
where is explained the benefit offered by the vaccum.

I've made a test with my software:
before vaccuming: 478 "operations"
after vaccuming: 1378 "operations"

Good, but the documentation reports:
- Beginning in PostgreSQL 7.2, the standard form of VACUUM can run in
parallel with normal database operations. If my DB is a 7.1.3 what
happens?

- Prior to PostgreSQL 7.2, the only defense against XID wraparound was to
re-initdb at least every 4 billion transactions. And in the 7.1.3

Is it safe to run the vaccum on a production DB?

I've also planned to setup a ramdisk to improve the performances.. is
it a good choice?

TIA, Auri