your tables aren't normalized; duplicate data is a big no-no. i'll assume
that each computer has only one owner, but it seems safer to assume that one
owner could have many (more than one) computers. suggest the following
tables, as

tblOwners (or tblCustomers, perhaps?)
OwnerID (primary key)
OwnerFirstName
OwnerLastName
OwnerPhone
(if an owner may have more than one phone number, you need a separate table
for phone numbers, with OwnerID in it as a foreign key.)

tblComputers
ComputerSerNum (pk)
ComputerName
OwnerID (foreign key from tblOwners)
OperatingSystem
ServicePacks
DatePurchased
(note:  if you need to list multiple service packs for one computer, then
you need a separate table for service packs, with ComputerSerNum as a
foreign key in it. ditto for operating system.)
(also note:  serial number should be a unique value, so it makes a good
natural key. if you don't want to use it as primary key for some reason, add
another field with autonumber data type to serve as your primary key field;
you could call it ComputerID.)

tblTickets
TicketID (pk)
ComputerID (fk from tblComputers)
(other fields that describe a specific trouble ticket)

you don't enter the owner information into a ticket. each ticket record is
linked to a specific computer record, and each computer record is linked to
a specific owner - so you can display the owner info for a specific ticket
on a specific computer any time you need to. that's the whole point of a
relational database model:  you enter each data element only once, and since
related data elements have a pk/fk link, you can pull them together in
multiple ways for whatever data entry/display purposes you need.

hth